We compared two cementless femoral components, the 'isoelastic' Butel stem and the more rigid PCA design, in a randomised, prospective study of 56 patients with a mean follow-up of 4 years (2 to 5). Patients were matched in 28 pairs, and one of each pair was treated with each femoral component. The isoelastic stem gave fewer signs of stress shielding radiologically, but both the Harris hip score and the visual analogue pain scale showed significantly inferior results at the two-year and three-year follow-up. The overall failure rates for the femoral components were 43% for the Butel and 11% for the PCA. These results contrast with those of earlier experimental and clinical studies, in which isoelastic properties appeared to be advantageous. This review emphasises the importance of controlled studies before an altered or new design of prosthesis is released on to the market for general use.
We used the stainless steel cable grip system described by Dall and Miles in 1983 to fix trochanters in 40 hips after total arthroplasty with trochanteric osteotomy. The cable broke in 32.5% of the hips; the trochanter failed to unite in 37.5%. Significantly more cables broke when placed inside the femoral canal than when the cable was placed round the femoral shaft (58% as against 9.5%, difference p less than 0.01). The high incidence of breakage may have resulted from contact between the stainless steel cable and the titanium prosthesis, from the acute angulation, or because of the lower fatigue strength of stainless steel. Better results have been obtained using cables with a higher fatigue strength, passed outside the proximal femur.
We followed prospectively 69 patients with 78 proximal femoral allografts performed for revision of total hip arthroplasty for an average of 36 months (range 29 to 68). Large fragment proximal femoral allografts and cortical strut allografts were successful in 85%. Grafts smaller than 3 cm in length (calcar grafts) were clinically successful in 81%, but 50% underwent significant radiographic resorption. We conclude that large proximal femoral allografts and cortical strut allografts provide dependable reconstruction of bone stock deficiencies during revision total hip arthroplasty.
A method of performing a biplanar intracapsular trochanteric osteotomy with a Gigli saw was designed and tested prospectively in 431 cases of Charnley low friction arthroplasty. Three methods of trochanteric reattachment were tested, and a double cross-over wire with a compression spring was best; this method was successful in 222 out of 226 patients (98.2%), of which half were revision operations. Adduction seemed to be the main movement leading to trochanteric detachment.
Immunosuppression following intra-articular injections of steroid into the hip may interfere with asepsis in a subsequent total hip arthroplasty (THA). We have undertaken a retrospective, matched, cohort study of infective complications after THA, in 40 patients who had received such an injection and 40 who had not. In the injection group there were five revisions, four of which were for deep infection. There were none in the matched group. The overall rate of revision in our database of 979 primary THAs was 1.02%. Six additional patients who had received injections underwent investigation for infection because of persistent problems in the hip as compared with one in the control group.
Instruments used in surgery which rotate or vibrate at a high frequency can produce potentially contaminated aerosols. Such tools are in use in cemented hip revision arthroplasties. We aimed to measure the extent of the environmental and body contamination caused by an ultrasound device and a high-speed cutter. On a human cadaver we carried out a complete surgical procedure including draping and simulated blood flow contaminated with Environmental contamination was present in an area of 6 x 8 m for both devices. The concentration of contamination was lower for the ultrasound device. Both the ultrasound and the high-speed cutter contaminated all members of the surgical team. The devices tested produced aerosols which covered the whole operating theatre and all personnel present during the procedure. In contaminated and infected patients, infectious agents may be present in these aerosols. We therefore recommend the introduction of effective measures to control infection and thorough disinfection of the operating theatre after such procedures.
The purpose of this study was to establish whether
exploration and neurolysis is an effective method of treating neuropathic
pain in patients with a sciatic nerve palsy after total hip replacement
(THR). A total of 56 patients who had undergone this surgery at
our hospital between September 1999 and September 2010 were retrospectively identified.
There were 42 women and 14 men with a mean age at exploration of
61.2 years (28 to 80). The sciatic nerve palsy had been sustained
by 46 of the patients during a primary THR, five during a revision
THR and five patients during hip resurfacing. The mean pre-operative
visual analogue scale (VAS) pain score was 7.59 (2 to 10), the mean
post-operative VAS was 3.77 (0 to 10), with a resulting mean improvement
of 3.82 (0 to 10). The pre- and post-neurolysis VAS scores were
significantly different (p <
0.001). Based on the findings of
our study, we recommend this form of surgery over conservative management
in patients with neuropathic pain associated with a sciatic nerve
palsy after THR. Cite this article:
Impaction bone grafting for the reconstitution
of bone stock in revision hip surgery has been used for nearly 30 years.
Between 1995 and 2001 we used this technique in acetabular reconstruction,
in combination with a cemented component, in 304 hips in 292 patients
revised for aseptic loosening. The only additional supports used
were stainless steel meshes placed against the medial wall or laterally
around the acetabular rim to contain the graft. All Paprosky grades
of defect were included. Clinical and radiographic outcomes were
collected in surviving patients at a minimum of ten years after
the index operation. Mean follow-up was 12.4 years ( Cite this article:
Femoral impaction bone allografting has been developed as a means of restoring bone stock in revision total hip replacement. We report the results of 75 consecutive patients (75 hips) with a mean age of 68 years (35 to 87) who underwent impaction grafting using the Exeter collarless, polished, tapered femoral stem between 1992 and 1998. The mean follow-up period was 10.5 years (6.3 to 14.1). The median pre-operative bone defect score was 3 (interquartile range (IQR) 2 to 3) using the Endo-Klinik classification. The median subsidence at one year post-operatively was 2 mm (IQR 1 to 3). At the final review the median Harris hip score was 80.6 (IQR 67.6 to 88.9) and the median subsidence 2 mm (IQR 1 to 4). Incorporation of the allograft into trabecular bone and secondary remodelling were noted radiologically at the final follow-up in 87% (393 of 452 zones) and 40% (181 of 452 zones), respectively. Subsidence of the Exeter stem correlated with the pre-operative Endo-Klinik bone loss score (p = 0.037). The degree of subsidence at one year had a strong association with long-term subsidence (p <
0.001). There was a significant correlation between previous revision surgery and a poor Harris Hip score (p = 0.028), and those who had undergone previous revision surgery for infection had a higher risk of complications (p = 0.048). Survivorship at 10.5 years with any further femoral operation as the end-point was 92% (95% confidence interval 82 to 97).
We performed revision surgery for infected arthroplasty in 98 hips (96 patients). In 28 hips infection persisted. Of the remaining 70 hips, 61 (87%) were reviewed after a mean interval of 5.9 years (1 to 17). Infection occurred in 10% of these after three years and in 26% after ten years. The infection rate after initially successful revision for septic arthroplasty is higher than after revision for aseptic loosening and the risk of developing infection continues for many years.
We report the results of 24 acetabular reconstructions in which cemented polyethylene cups and tamped corticocancellous allografts were used for severe acetabular bone deficiency. Eleven hips had type-II (cavitary) bone deficiency and 13 had type-III (combined) defects. At a mean follow-up of 5.8 years, two components had migrated more than 5 mm and had accompanying radiolucent zones of more than 2 mm width. A radiolucency 5 mm wide was also seen in zone III of an acetabular implant which had not migrated. None of the patients had required revision because of loosening or infection.
We studied 16 femora retrieved at post-mortem from symptomless patients who had a satisfactory cemented total hip arthroplasty from two weeks to 17 years earlier, with the aim of delineating the initial mechanisms involved in loosening. Only one specimen showed radiographic evidence of loosening; the other 15 were stable to mechanical testing at 17.0 Nm of torque. In all 16 specimens, the cement-bone interface was intact with little fibrous tissue formation. By contrast, separation at the cement-prosthesis interface and fractures in the cement mantle were frequent. The most common early feature was debonding of the cement from the metal, seen at the proximal and distal ends of the prosthesis. Specimens which had been in place for longer also showed circumferential fractures in the cement, near the cement-metal interface, and radial fractures extending from this interface into the cement and sometimes to the bony interface. The most extensive cement fractures appeared to have started at or near sharp corners in the metal, or where the cement mantle was thin or incomplete. Fractures were also related to voids in the cement. The time relationship in this series suggested that long-term failure of the fixation of cemented femoral components was primarily mechanical, starting with debonding at the interface between the cement and the prosthesis, and continuing as slowly developing fractures in the cement mantle.
Total hip replacement using an alumina head and socket and a titanium alloy stem is evaluated in a series of patients under 50 years of age. Between April 1977 and December 1986, 86 such replacements were performed in 75 patients, but mainly because patients had difficulty travelling from Africa, only 71 hips were followed up adequately; of these, 56 were primary procedures and 15 revisions. Survivorship analysis showed that 98% of the prostheses were retained for 10 years. On clinical and radiological examination 51 of the 71 hips were stable and acceptable, 15 had radiological changes on the acetabular side, and one on the femoral side; four other cases had clinical and radiological changes suggesting impending failure, possibly because fixation of the socket was inadequate. There were no differences between the results of the primary procedures and those of revisions. In these young patients, the results seem better with alumina-on-alumina hips than with other varieties, possibly because of their remarkably low wear.
We reviewed 134 primary noncemented porous-coated total hip replacements in 125 patients: 64 were DePuy AML prostheses, 20 were Howmedica PCA and 50 were Implant Technology LSF. The prostheses had been in situ for an average of 36 months, 40 months and 24 months respectively. The average pre-operative Harris hip scores were 38.2 for AML, 33.2 for PCA, and 41.0 for the LSF prostheses. The average postoperative scores were 80.7 for AML, 83.8 for the PCA, and 91.5 for LSF. Thigh or groin pain associated with the prosthesis was present in 30% of AML, 30% PCA and 8% of the LSF cases. The clinical and radiographic review showed better early results with the LSF prostheses than the others; this seemed to be related to the implant design, which provided improved initial stability and more physiological transfer of load.
We reviewed the results of 14 total hip replacements in patients with juvenile chronic arthritis. The mean age at operation was 16 years (range 12 to 22 years); follow-up was from four to 11 years (mean 8.5 years). Postoperatively pain relief was sustained in all but one hip, while movement generally remained significantly restricted. No hip has as yet required a revision operation, although eight hips (57%) show radiological changes suggestive of impending failure. All patients had severe polyarticular involvement with associated restriction of locomotor activity. Potential causes contributing to loosening such as continuing diaphyseal bone growth and increased immunocompetence in adolescence are discussed.