Unicompartmental knee replacement (UKR) is associated with higher revision rates than total knee replacement and it has been suggested that surgeons should receive specific training for this prosthesis. We investigated the outcome of all UKR in a district general hospital over ten years.

All patients who had received UKR from 2003 to 2013 were identified from theatre records, as were all revision knee arthroplasties. We contacted all patients (or their GP) with no known revision to ascertain UKR status. A life table analysis was used for three categories: all surgeons and types of UKR, Oxford UKR only and Oxford UKR by surgeons with specific training.

There were 319 UKR (one loss to follow up), four types of prosthesis, 21 failures and a 5-year cumulative survival rate of 91.54%. There were 310 Oxford UKR with 17 failures and 5-year survival 93.56%. Surgeons with training in use of Oxford UKR completed 242 replacements with 10 failures and 5-year survival of 95.68%.

In comparison with results for Oxford UKR in 11th annual NJR report, our results are satisfactory and support continued use of this prosthesis in a non-specialist centre. Our established programme of surveillance will monitor the survival of UKR in our hospital.

Aims

Several national studies have shown that the rates of joint replacement are rising and this increase may be greater than that expected by population ageing. The aim of this study was to assess local rates of joint replacement at a district general hospital (DGH) and to investigate whether there had been a change in pre-operative functional status of patients over the study period to account for any change in rates of arthroplasty.

Introduction

Large head total hip arthroplasty (THA) reduces dislocation rates and provides a theooretically larger range of motion. We hypothesised that this would translate into greater improvement in functional scores when compared to 28mm metal-on-polyethylene THA at 5 years. We believe ours to be the first in vivo comparison study.

Introduction

Traditional TKR designs exhibit abnormal and unpredictable kinematics: with posterior subluxation in extension and anterior slide with flexion. These can contribute to restricted knee flexion and reduced quadriceps efficiency. Newer designs attempt to provide “guided motion” with the aim of mimicking normal knee kinematics. The Journey (Smith & Nephew) BCS TKR incorporates both an anterior and a posterior cam/post mechanism while Triathlon PS TKR (Stryker) incorporates a posterior cam/post mechanism. This study compares the in-vivo kinematics of these two designs and compares it with normal knee.

OBJECTIVE

To examine the short term patient assessed functional results of the Journey BCS ¯(Smith & Nephew) and Triathlon ¯(Stryker Orthopaedics, Mahwah, NJ) total knee replacements when compared to the Scorpio ¯(Stryker) total knee replacement using a multi-surgeon case control design in a single centre.

Aim: To evaluate the possible increase to surgical/operating room capacity by increasing the percentage of uncemented total hip replacement

Introduction: Globally there is growing demand for increased efficiency and productivity from medical care. In hip arthroplasty there has been increased interest in the use of uncemented components with several studies and registry data showing them to perform well clinically 1, 2. One concern with their increased use has been increased costs 3. We have examined the issue of operative timing and discuss the possible role these components may have in increasing theatre utilisation times and so offsetting their cost.

Methods: This was a prospective, cohort study of every hip replacement performed in a dedicated arthroplasty unit within a district general hospital over one year. All care of patients was standardised using pathways, including all surgeons using a posterior approach with posterior repair. This allowed us to determine the relative effect of prosthesis type on quality, safety and efficiency. Demographic, anaesthetic, operative and timing details on all cases performed were collected prospectively and independently of the surgical team. Patients were reviewed at six weeks and one year post op. All readmissions to any hospital were noted and any further surgery recorded.

Results: There were 1248 cases performed in one year. Of these 194 were uncemented (both components) and 286 cemented total hip replacements. Patient demographics were similar (mean age 70.9 years, range 28–92). Both hip types showed no difference in quality or safety factors as assessed by hip scores, patient mobilisation times, complication rates or revision rates. The only difference was in the surgical times. These were (in minutes):

– Mean Standard Deviation Minimum Maximum

(*p< 0.0005)

Conclusions: Our data demonstrates an average time saving of 17 minutes per case performed. If, over the next year, we converted to all uncemented hips we would release 136 hours of operative time, giving an opportunity to get 100 more cases done. This represents a 20% increase in productivity with no compromise to safety or quality.

To establish the efficacy of a new arthroscopic technique, for the treatment of stiffness after TKR.

Introduction: The usual surgical procedure for stiffness after a total knee replacement is an open arthrolysis, though an arthroscopic procedure can be considered within six months of the index surgery. We have evolved a new procedure of capsulectomy and anterior release which can be used at any time after TKR in patients with a reduced range of movement (ROM).

Methods: 22 patients (10 women and 12 men) underwent arthroscopic capsulectomy and anterior release for the treatment of loss of movement after TKR. The mean age was 62 (range 47–71 yrs). Mean time between TKR and arthrolysis was 27 months (range 3–54). Indication for the arthroscopic procedure was decreased ROM following TKR. Arthroscopy was performed using anteromedial and anterolateral portals. The dense scar tissue was divided and completely excised arthroscopically. ROM was assessed pre-operatively, immediately post-operatively and at 2, 6, 12 weeks, 6 months and 1 year. The Oxford Knee Score (OKS) and American Knee Society Score (AKSS) were used pre-operatively and at 6 months and 1 year post-operatively.

Results: Pre-operatively mean flexion was 50 degrees (Range 20–90°). Post-operatively it was 94.5° (Range 55–125°). At 1 year this was maintained. The mean OKS pre-operatively was 18.4 (range 8–39). At 1 year it was 29.8 (range 9–39). The AKSS (knee and functional components) showed a similar improvement. The mean knee score increased from 47.3 pre-operatively to 71.6 at 1 year. The functional score rose from a mean of 51.3 pre-operatively to 76.9 at 1 year.

Conclusions: Our technique of arthroscopic capsulectomy and anterior release for the treatment of stiffness following TKR is both successful and safe. At 1 year post-operatively the patients have maintained an increased ROM and significantly improved Oxford and American Knee Society Scores.

Minimally invasive approaches to the hip may be divided into two categories: single mini-incisions derived from standard approaches and two-incision approaches designed specifically for minimally invasive total hip replacement. The authors have a number of specific concerns about the latter based on its apparent transgression of basic surgical principles and favour a mini-lateral approach to the hip which they describe and review.

The two-incision approach requires two short (2–5cm) incisions from two different directions. Unlike other minimally invasive techniques, these incisions run close to the major neurovascular structures, which have been damaged. Visibility is limited as demonstrated by the need for navigation systems and illuminated retractors by some groups. Accurate resection of the femoral neck is obscured by the presence of the femoral head. Precise siting of the socket may be compromised by poor visibility. Most series accomodate only the use of uncemented components. Claims for more rapid mobilisation appear to depend more on anaesthetic rather than surgical technique.

We have developed the mini-lateral approach to the hip, in parallel with others, over the last five years. It is a scaled-down version (< 10cm) of the Hardinge approach which has been used successfully for 25 years. It relies on a precise appreciation of the regional anatomy requires no additional equipment and avoids the problems posed by the two-incision approach. A short video presentation will be given.

We present a consecutive retrospective series of 99 patients having 103 cemented C-stem THA for OA over a three-year period. Patients were assessed for duration of surgery, blood loss and length of postoperative stay. At follow-up (mean 18/12) they were assessed using the Oxford Hip Score, radiographic analysis and their incisions were measured. No hips have been revised and none are considered to be at risk. No nerve or vascular injuries have been reported.