Satisfaction following total knee replacement (TKR) surgery remains suboptimal at around 80%. Prediction of factors influencing satisfaction may help manage expectations and thus improve satisfaction. We investigated preoperative variables that estimate the probability of achieving a successful surgical outcome following TKR in several outcomes important to patients. 9 pre-operative variables (easily obtained on initial consultation) of 591 unilateral TKRs were selected for univariant then multivariant analyses. These variables included Oxford Knee Score (OKS), age, sex, BMI, ASA score, pain score, mobility aids, SF12 PCS & SF12 MCS. Using the relative predictive strengths of these variables we modeled the probabilities a successful result would be achieved for 6 patient reported outcomes at 3 and 12 months following surgery. These were ‘Excellent/good OKS’, ‘Mild/no pain’, ‘Walking without/at first a limp’, ‘No/little interference with normal work’, ‘Kneeling with little/no difficulty’ and ‘Satisfaction with surgery’.Introduction & aims
Method
The risk of hip dislocation after revision total hip arthroplasty is up to 20% following surgery for periprosthetic fractures. A technique was developed by the senior authors, involving a transtrochanteric osteotomy and superior capsulotomy to attempt to minimise this risk(1). This prospective study examines a cohort of 40 patients undergoing this novel technique, which involves extending the fracture proximally to the tip of the greater trochanter. This is then extended into the soft tissues in the mid lateral plane as a split of the glutei and a minimally superior capsulotomy (preserving the anterior and posterior capsule). This allows for revision of the femoral component, and retention of the socket and liner. The outcomes of interest to the authors were dislocation rates, clinical outcome measured using the Oxford hip score. These were assessed along with X-ray imaging at 1, 2 and 5-year intervals to confirm fracture union and measure stem subsidence.Introduction
Methods
We conducted a randomised controlled trial to assess the accuracy
of positioning and alignment of the components in total knee arthroplasty
(TKA), comparing those undertaken using standard intramedullary
cutting jigs and those with patient-specific instruments (PSI). There were 64 TKAs in the standard group and 69 in the PSI group. The post-operative hip-knee-ankle (HKA) angle and positioning
was investigated using CT scans. Deviation of >
3° from the planned
position was regarded as an outlier. The operating time, Oxford
Knee Scores (OKS) and Short Form-12 (SF-12) scores were recorded.Aims
Patients and Methods
The aim of this study was to compare a single-incision minimally invasive (MI) posterior approach with a standard posterior approach in a double-blind prospective randomised controlled trial. A pilot study was carried out to assess the efficacy of the MI approach. Primary total hip replacements meeting the inclusion criteria were randomised to either the MI approach or the standard posterior approach. Patients were blinded to allocation. Patients were scored by a blinded physiotherapist pre-operatively, at Day 2, 2 weeks and 6 weeks. The primary outcome measure was function, assessed using the Oxford hip score, SF-12 questionnaire, Iowa score, 6-minute walk test and the number of walking aids required after 2 and 6 weeks post-operatively. Secondary outcomes were complication rates, patient satisfaction, soft tissue trauma and radiographic analysis.Aim
Method
We undertook a randomised controlled trial to
compare the piriformis-sparing approach with the standard posterior approach
used for total hip replacement (THR). We recruited 100 patients
awaiting THR and randomly allocated them to either the piriformis-sparing
approach or the standard posterior approach. Pre- and post-operative
care programmes and rehabilitation regimes were identical for both
groups. Observers were blinded to the allocation throughout; patients
were blinded until the two-week assessment. Follow-up was at six
weeks, three months, one year and two years. In all 11 patients
died or were lost to follow-up. There was no significant difference between groups for any of
the functional outcomes. However, for patients in the piriformis-sparing
group there was a trend towards a better six-minute walk test at
two weeks and greater patient satisfaction at six weeks. The acetabular
components were less anteverted (p = 0.005) and had a lower mean
inclination angle (p = 0.02) in the piriformis-sparing group. However,
in both groups the mean component positions were within Lewinnek’s
safe zone. Surgeons perceived the piriformis-sparing approach to
be significantly more difficult than the standard approach (p =
0.03), particularly in obese patients. In conclusion, performing THR through a shorter incision involving
sparing piriformis is more difficult and only provides short-term
benefits compared with the standard posterior approach.
The aim of this study was to compare a single-incision minimally invasive posterior approach with a standard posterior approach in a double-blind prospective randomised controlled trial. A pilot study was carried out to assess the efficacy of the minimally invasive (MI) approach. The protocol described in the CONSORT statement was used as a template for the study design. 100 Primary total hip replacements meeting the inclusion criteria were randomised in theatre to either the MI approach (using a small incision with preservation of piriformis and distal aspect of quadratus femoris) or the standard posterior approach. Hips meeting the inclusion criteria were randomised in theatre using sealed identical opaque envelopes. Patients were blinded to allocation and all patients remained in the group they were allocated to. Pre and post-operative care programmes were identical. Patients were scored by a blinded research physiotherapist pre-operatively, at Day 2, 2 weeks, 6 weeks and 3 months post operation. The primary outcome measure was function, assessed using the Oxford hip score, SF-12 questionnaire, Iowa score, 6-minute walk test and the number of walking aids required after 2 and 6 weeks post operatively. Secondary outcomes were complication rates, patient satisfaction, difficulty of the procedure as perceived by the surgeon, soft tissue trauma (CRP and blood loss) and radiographic analysis. 50 patients were recruited to each group. There was no difference in demographics Mean incision length was 12.8cm and 19.1cm respectively. There was no statistically significant difference in operation time, post-op functional recovery (ILOA score) or length of stay. Pain (VAS) was similar post-operatively, and at 6 and 12 weeks. There was no significant difference in 10 metre walking speed or 6 minute walking distance at 2, 6 or 12 weeks; nor was there a difference in Oxford hip score, patient satisfaction with surgery (VAS), or SF-12 score at 6 or 12 weeks. Blood loss, fall in haematocrit, transfusion rate and CRP rise were similar. There was no significant difference in cementation of the stem (Barrack) or cup position (Dorr). There was one death from PE in the MIS group and one deep infection in the standard group. There was one dislocation in the standard group. The only statistical difference between the groups was less dependence on walking aids at 2 and 6 weeks in the MIS group; there was no difference at 12 weeks. MIS surgery is safe, and may allow earlier independent mobility after THR. However, the claims of significantly reduced pain, less morbidity, better function and improved patient satisfaction appear to be unfounded.
Despite initial enthusiasm for minimally invasive total hip replacements (THR), there has been a marked paucity of level 1 evidence studies assessing it. 100 patients fulfilling the inclusion criteria were randomised in theatre to a standard posterior or muscle-sparing short incision (MIS) approach. A hybrid hip replacement was used routinely. Post-operative management was the same. Follow-up occurred at 2, 6 and 12 weeks. Patients, as well as functional and radiographic assessors were blinded. 50 patients were recruited to each group. There was no difference in demographics Mean incision length was 12.8cm and 19.1cm respectively. There was no statistically significant difference in operation time, post-op functional recovery (ILOA score) or length of stay. Pain (VAS) was similar post-operatively, and at 6 and 12 weeks. There was no significant difference in 10 metre walking speed or 6 minute walking distance at 2, 6 or 12 weeks; nor was there a difference in Oxford hip score, patient satisfaction with surgery (VAS), or SF-12 score at 6 or 12 weeks. Blood loss, fall in haematocrit, transfusion rate and CRP rise were similar. There was no significant difference in cementation of the stem (Barrack) or cup position (Dorr). There was one death from PE in the MIS group and one deep infection in the standard group. There was one dislocation in the standard group. The only statistical difference between the groups was less dependence on walking aids at 2 and 6 weeks in the MIS group; there was no difference at 12 weeks. MIS surgery is safe, and may allow earlier independent mobility after THR. However, the claims of significantly reduced pain, less morbidity, better function and improved patient satisfaction appear to be unfounded.
We treated 34 patients with recurrent dislocation of the hip with a constrained acetabular component. Roentgen stereophotogrammetric analysis was performed to assess migration of the prosthesis. The mean clinical follow-up was 3.0 years (2.2 to 4.8) and the radiological follow-up was 2.7 years (2.0 to 4.8). At the latest review six patients had died and none was lost to follow-up. There were four acetabular revisions, three for aseptic loosening and one for deep infection. Another acetabular component was radiologically loose with progressive radiolucent lines in all Gruen zones and was awaiting revision. The overall rate of aseptic loosening was 11.8% (4 of 34). Roentgen stereophotogrammetric analysis in the non-revised components confirmed migration of up to 1.06 mm of translation and 2.32° of rotation at 24 months. There was one case of dislocation and dissociation of the component in the same patient. Of the 34 patients, 33 (97.1%) had no further episodes of dislocation. The constrained acetabular component reported in our study was effective in all but one patient with instability of the hip, but the rate of aseptic loosening was higher than has been reported previously and requires further investigation.
