Abstract
Eighty-nine patients (8 males, 81 females) with an average age of 52 years had 119 high dislocations (Crowe IV, 30 bilateral and 59 unilateral). The patients underwent 118 total hip arthroplasties between 1970 and 1986 using original or modified Charnley prostheses. Only 39 patients had not had a previous operation. Pain in the hip associated with stiffness and limitation in activity was the main indication for surgery. Back or knee pain was the chief complaint of 11 patients. Pre-operatively and post-operatively, a thorough assessment of the patients was made including hips, pelvis lumbosacral spine, knee, leg length discrepancy and static body balance.
The operation was performed through a transtrochanteric approach. A small socket was always inserted and cemented into the true acetabulum augmented by an autogenous graft, and a straight femoral component implanted at the level of the lesser trochanter. Muscle releases and tenotomies were not performed. Twenty-nine patients (35 hips) had died or were lost to follow-up. Sixty patients were still alive at the last examination in 1996, and regularly seen with a mean follow-up of 16 years. The mean follow-up of the whole series was 12.8 years.
At the last examination, clinical results according to the d’Aubigne rating system were classified as excellent 59.3%, very good 15.2%, good 15.2%, fair 5.1%, and poor 5%. Only 10 patients had a persistent waddling gait and a positive Trendelenburg sign. The results were slightly less good when a major femoral angulation needed an alignment osteotomy.
One femoral and seven acetabular loosenings were revised. In addition, five hips were revised for severe polyethylene wear and osteolysis before definite loosening, and two hips for heterotopic ossifications. The rate of revision was 12.7%. At twenty years, the survival rate was 99% for the femoral component and 87% for the socket, cemented fixation as end point, whereas the cumulative survival rate of the prosthesis was 78%, revision as end point.
The leg shortening, mean 4.84 cm (range 3-8 cm), was accurately corrected 63 times and within 1 cm 42 times. The lengthening was an average of 3.80 cm (2 to 7 cm). Leg length discrepancy was, on the whole, reduced as much as possible (mean 2.6 cm pre-operatively, 0.4 cm post-operatively). Of the 18 pre-operative painful knees, 10 were greatly improved, but four of these needed an operation.
Lateral pelvic tilt was corrected in more than 50%, pelvic frontal asymmetry was substantially reduced, as well as lordosis and lateral curve of the lumbar spine. As a result, low back pain has been relieved in 40 patients, but two required a laminectomy for a lumbar canal stenosis.
Total hip arthroplasty on high riding hips may be a wonderful operation, but this operation is full of pitfalls, technically demanding, and may represent a serious risk of complication. A successful result depends on a complete pre-operative assessment of the patient, a perfectly performed surgical procedure, and a reasonable selection of its indications.
The abstracts were prepared by David P. Davlin. Correspondence should be addressed to him at the Orthopedic Clinic Bulovka, Budínova 2, 18081 Prague 8, Czech Republic.
