header advert
Results 1 - 10 of 10
Results per page:
Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_2 | Pages 47 - 47
10 Feb 2023
Reason S Wainwright C
Full Access

Little guidance exists in the current literature regarding which patient recorded outcome measures (PROMs) are most clinically appropriate following anterior cruciate ligament reconstruction (ACL) surgery, and what results surgeons should expect or accept. Many PROMs have been validated, but their “ideal” results have not been published, limiting a surgeon's ability to compare their patients’ outcomes with those of their colleagues.

We undertook a systematic review of PROMs for ACL to look at common usage and outcomes. After appropriate paper selection, we then undertook a pragmatic meta-analysis (i.e., including all papers that fulfilled the selection criteria, regardless of CONSORT status) and calculated weighted mean outcome scores and standard deviations for the most commonly used PROMs.

A comprehensive literature search of all English articles of PubMed and other sources including search terms (‘Patient related outcome measure’ or ‘PROM’) AND ‘anterior cruciate ligament’ (limited to abstract/title) yielded 722 articles. Title review narrowed this to 268, and abstracts review to 151, of which 88 were included in our meta-analysis. Weighted mean and standard deviations were calculated for IKDC, KOOS, Lysholm, Teneger and “VAS Pain” PROMs as the most commonly reported. We identified significant, novel findings relating to selected PROMs and (i) demographics including age, gender and body mass index, (ii) surgical factors including bundle count, strand count, and graft type, and (iii) post operative complications.

We clarified the most commonly used PROMs for ACL, and their weighted means and standard deviations. This will allow surgeons to compare results with colleagues, ensuring they meet international levels of quality in PROMs. We have also updated which patient and operative factors have an impact on PROMs scoring to allow for population variance.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XLI | Pages 78 - 78
1 Sep 2012
Wainwright C Dempsey S
Full Access

Assessing risk is a key skill for all surgeons, playing a vital role in such diverse settings informed consent, audit and surgical planning. We undertook this study to define what is an acceptable level of risk for orthopaedic surgeons undertaking lower limb arthroplasty in today's medicolegal climate.

We surveyed all consultants and trainees registered with the NZOA and asked them what change in their complication rate would cause them to consider changing their practice. We also asked them how certain they would have to be that this change was real and not simply due to chance (the so-called “cluster effect”). The specific complications we considered were DVT/PE, dislocation of total hip replacement or deep infection in lower limb arthroplasty patients. This allowed us to calculate with 95% accuracy the levels of complication surgeons would deem unacceptable.

Using Cochrane's criteria for statistically valid survey results we obtained a greater than 95% representative sample. From these responses we calculated levels of complication which would worry the “average” surgeon (median value), the “vast majority” (95%) of surgeons and a change in complication rate which would be required to satisfy “statistical significance” (i.e. the level set literature proof with p<0.05 and power of 0.8). When considering deep infection following hip or knee arthroplasty: using a baseline of 0.9% as an average published rate, the average surgeon would consider changing their practice if their rate reached 2.5% and 95% of surgeons would consider changing if their rate reached 5%. For hip dislocation the baseline was set at 2.5% with the average surgeon intervening if their rate rose to 4% and the vast majority of surgeons intervening at 10%. For fatal PE the baseline was given as 0.2% with the average surgeon auditing their practice at 0.8% and the vast majority of surgeons concerned with a rate of 2.2% or higher. No difference was found in consultant/trainee responses except in the reason given for use of thromboprophylaxis where consultants used it for prevention of fatal PE and registrars for non-fatal PE.

These results could be used both as a potential guide for trainees and consultants in audit and also in guiding the use of, for instance, thromboprophylaxis where the “number needed to treat” for low molecular weight heparin to prevent one fatal pulmonary embolus in a year would necessitate national use/guidelines.


The Journal of Bone & Joint Surgery British Volume
Vol. 93-B, Issue 10 | Pages 1411 - 1415
1 Oct 2011
Wainwright C Theis J Garneti N Melloh M

We compared revision and mortality rates of 4668 patients undergoing primary total hip and knee replacement between 1989 and 2007 at a University Hospital in New Zealand. The mean age at the time of surgery was 69 years (16 to 100). A total of 1175 patients (25%) had died at follow-up at a mean of ten years post-operatively. The mean age of those who died within ten years of surgery was 74.4 years (29 to 97) at time of surgery. No change in comorbidity score or age of the patients receiving joint replacement was noted during the study period. No association of revision or death could be proven with higher comorbidity scoring, grade of surgeon, or patient gender.

We found that patients younger than 50 years at the time of surgery have a greater chance of requiring a revision than of dying, those around 58 years of age have a 50:50 chance of needing a revision, and in those older than 62 years the prosthesis will normally outlast the patient. Patients over 77 years old have a greater than 90% chance of dying than requiring a revision whereas those around 47 years are on average twice as likely to require a revision than die. This information can be used to rationalise the need for long-term surveillance and during the informed consent process.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_III | Pages 381 - 381
1 Jul 2011
Wainwright C Theis J Williams S
Full Access

Statistics New Zealand states “Over the next five decades the 65+ dependency ratio is projected to more than double, from 18 (people aged 65+ years) per 100 (people aged 15 – 64 years) in 2006 to 45 per 100 in 2061. This means that for every person aged 65+ years, there will be 2.2 people in the working-age group in 2061, compared with 5.4 people in 2006 “. This will have a profound impact on health care, specifically in those fractures sustained by the elderly e.g. fractured neck of femur (#NOF).

Also at present little is proven regarding outcome following #NOF in the New Zealand population. These two factors (population change and patient outcome) led to disagreement and healthy debate at the 2008 NZOA ASM. After a pilot study in Dunedin we have examined national electronic records of 52,456 patients presenting with a first admission due to #NOF over the last 20 years.

The mean age at which a patient sustained their first #NOF was around 80 and 71% of these patients have since died. Approximately 10% of patients had a subsequent readmission for #NOF. There was a trend for increasing age over the last twenty years proportional to the increased average age of the general population. One year survival was 75% and mean survival was 3½ years with a third of patients living longer than six years. We found differences in outcome for gender and fracture type (intracapsular vs. extracapsular). Our patients also showed a trend to higher survival risk ratios (i.e. they are clinically “sicker” than they used to be). The incidence of #NOF has increased over the last 20 years with a projected doubling in the number of cases (to 5600 per year) at around 25yrs from now based on the most conservative estimates.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_III | Pages 274 - 274
1 Jul 2011
Kakwani R Wainwright C Tawari G Kashyap S Roysam A Nanu A
Full Access

Purpose: A single blind prospective randomised controlled trial comparing the Metal-on-polyethylene articulation with the metal-on-metal articulation in THA.

Method: The clinical and radiological findings of the consecutive patients who were enrolled in the RCT at the participating centres were recorded prospectively. The clinical evaluation was performed with the Harris scoring system as well as the Oxford Hip Scoring Sheet. The computer randomised option was revealed to the operative surgeon only after the patient was anaesthetised, during the recruitment period (June 1998 to July 2004). Of the total of 378 patients, 2 died prior to the final review and 63 were lost to follow-up. The final study group contained 315 patients, with 159 patients in the metal-on-polyethylene group and 156 patients in the metal-on-metal group.

Results: The indication for the hip arthroplasty for majority (309 patients) was primary osteoarthritis. The average age at the time of the surgery was 68.2 years and the average duration of follow-up was 85 months (42–115). There was an improvement of the Oxford hip scores from an average of 37 per-operatively to 16 postoperatively. The Harris hip scores also improved from an average of 47.0 pre-operatively to 87.3 post-operatively. The patient groups were statistically similar with respect to age, sex and duration of follow-up, and the final outcome scores revealed no statistical difference between the two groups.

Conclusion: The clinical results obtained with the use of the articulation are comparable to those obtained by the metal-on-polyethylene articulation encouraging the use of this alternative bearing surface.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 222 - 223
1 Mar 2010
Wainwright C Theis J Martin G Garneti N
Full Access

We determined the survival of primary total hip and knee replacements and patients who had undergone surgery between 1989 and 2007 in Dunedin with the aim to using these figures to provide information on

whether our arthroplasty population is changing,

what the likely future demands are on follow-up services,

whether we can predict which patients will require follow-up.

The initial search using records held by the audit department at Dunedin Hospital returned 6,328 patient records with total hip and knee arthroplasty between 1988 and 2007. These reports however, included many procedures which were neither hip/knee nor primary/revision total joint arthroplasty. The data was filtered, resulting in 4,773 hip and knee arthroplasties. The final data included 3194 primary total hip replacements and 1579 primary total knee replacements. Comorbidity scoring of these patients was also undertaken.

The mean age of patients who underwent primary hip replacement was 67.6 yrs (SD 12.4) and the mean age of patients who underwent a primary knee replacement was 70.8 yrs (SD 9.8). Around 25% of patients who have had a primary joint replacement died after a mean of 10 yrs after the operation. In the group of patients who died after 10 years, the mean age at surgery was around 74 years. The mean age at the time of death was around 80 years. No difference was found in the death rate, revision rate, and the combined outcomes with death or revision as the end point with respect to the following-THRs. TKR, the grade of the surgeon, the comorbidity score or in men vs. women as compared to the general population.

Patients over 59 years of age at time of primary arthroplasty have a > 90% chance of dying before the need for revision surgery. Patients of less than 51 years of age have a > 90% chance of requiring revision surgery. Patients of 55 years of age have a 50% chance of requiring revision surgery. In a setting of ongoing scarce resources symptomatic/questionnaire targeted follow-up with radiology may be the only long term viable solution.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 229 - 229
1 Mar 2010
Wainwright C Hodgson B Martin G
Full Access

There has been debate in the literature over the years regarding whether

rib resection, and

surgical approach have a significant impact on long term respiratory function following corrective surgery in idiopathic scoliosis patients.

We undertook a minimum 10 year review of prospective data in patients who had undergone corrective surgery for idiopathic scoliosis.

Patients had pre-operative, two year (where available) and 10 year follow-up respiratory function tests performed. Variables noted were sex, age at surgery, surgical approach, rib release (simple rib osteotomy, not resection), and percentage correction of curvature. All absolute respiratory function values were converted to percentages relative to a normal population of the same height, sex and age with reference to both arm span and height nomograms thus avoiding the need for a control group. Using accepted statistical norms and appropriate analysis we would be able to confirm a 10% difference in respiratory function.

A literature review was also undertaken as part of this study.

The only statistically significant change in respiratory function was a drop in FVC at 10 years in patients in whom a posterior approach had been used for correction without a rib release. In no other group (by other approach, sex, age, initial curvature, or curvature correction) was there a significant difference in long term respiratory function.

In our study the surgical approach did not have a significant impact on long term respiratory function. Rib release is a safe procedure to undertake as part of scoliosis correction.


The Journal of Bone & Joint Surgery British Volume
Vol. 91-B, Issue 7 | Pages 859 - 864
1 Jul 2009
Gwynne-Jones DP Garneti N Wainwright C Matheson JA King R

We reviewed the results at nine to 13 years of 125 total hip replacements in 113 patients using the monoblock uncemented Morscher press-fit acetabular component. The mean age at the time of operation was 56.9 years (36 to 74). The mean clinical follow-up was 11 years (9.7 to 13.5) and the mean radiological follow-up was 9.4 years (7.7 to 13.1). Three hips were revised, one immediately for instability, one for excessive wear and one for deep infection.

No revisions were required for aseptic loosening. A total of eight hips (7.0%) had osteolytic lesions greater than 1 cm, in four around the acetabular component (3.5%). One required bone grafting behind a well-fixed implant. The mean wear rate was 0.11 mm/year (0.06 to 0.78) and was significantly higher in components with a steeper abduction angle.

Kaplan-Meier survival curves at 13 years showed survival of 96.8% (95% confidence interval 90.2 to 99.0) for revision for any cause and of 95.7% (95% confidence interval 88.6 to 98.4) for any acetabular re-operation.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_II | Pages 337 - 337
1 May 2009
Wainwright C Jones DG King R
Full Access

The Morscher press fit acetabular component is a monobloc cup with the polyethylene bonded directly to a titanium mesh shell. There is little published data on the longevity of the Morscher cup apart from the designer’s series. It has been quite widely used in New Zealand since its introduction in 1993. The aim of this retrospective study was to provide an independent mid-term audit of the results of this cup in the New Zealand population.

A retrospective review was undertaken of all Morscher cups implanted at Dunedin Public Hospital or Mercy Hospital by 5 orthopaedic surgeons between 1994 and 1998 with a minimum follow-up of seven years. Clinical and radiological survey was performed with standardised scoring systems. A new method for measuring linear cup wear was developed due to the unusual geometry of the Morscher cup.

136 hips were replaced in 121 patients during the study period 101 were performed in private and 35 in public. Our follow up ranged from 7 to 11 years (mean 8.69). There were 73 males (85 hips) and 48 females (51 hips). The average age of the patients was 57.5yrs (SO 24.97). Pre operatively the mean Merle d’Aubigne score was 9.4 (SO 4.02) and post operatively it was 17.4 (SO 1.58 (p< 0.0001).

There were 2 early revisions: one at 3 days for instability post-operatively and one for an unrecognised intra-operative femoral fracture. One hip required a two stage revision for deep infection at 3 years. Two hips have been revised for polyethylene wear and osteolysis at 7 yrs and 9 yrs and one hip required bone grafting of a large acetabular osteolytic lesion with retention of the cup. A further 4 patients have significant osteolytic defects and 2 have minor osteolytic lesions.

Wear measurements in the unrevised hips have shown a mean linear wear rate of 0.079mm/yr (range 0.000 to 0.222mm). 33% of these hips have a wear rate of > 0.1 mm/yr and 25% have a wear rate of < 0.05mm/yr.

We have found excellent clinical results with the use of the Morscher cup in this relatively young and active cohort. A small group of patients, however, have shown higher wear rates or osteolysis, and we emphasise the importance of continuing radiological review.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 291 - 291
1 Sep 2005
Wainwright C Rao N Lawson D
Full Access

Introduction and Aims: Caudal and lumbar epidural steroid injections have had a contentious history in the treatment of lumbar radiculopathy. We set out to assess the efficacy of these injections with relation to key discriminators and to assess the safety of these injections.

Method: After a literature search highlighted several possible discriminators regarding outcomes for lumbar radiculopathy and surgery we undertook a pilot study to assess the above aims. This took the form of a retrospective telephone interview. When our pilot study reached statistical significance after only 25 patients, we undertook a retrospective study of all 138 patients who had received a caudal or epidural steroid injection for radiculopathy in the last eight years. This took the form of a postal questionnaire, with telephone interview follow-up. Appropriate statistical analysis was performed for the paired and non-paired data collected.

Results: Of the 138 patients, 105 could be traced and of these it was possible to compare caudal vs. lumbar epidural in 75. All other comparisons were made on the full available population (105). We showed a statistically significant difference in the following: (i) an overall reduction in pain scores from 7.78 to 5.16 (mean values, difference –2.62, p< 0.0001); (ii) an overall increase in march tolerance from 804m to 1788m (mean values, difference 984m, p,0.0001); (iii) smokers had a higher level of pain overall before, immediately after and longer term than non(N)smokers (mean values smokers vs. non are; before 8.25:7.4, immediately 5.75:4.269, long-term 6.708:5.173, p< 0.01). We found no significant difference between sexes, activity-provoked pain, cough/impulse pain, unemployment due to pain or number of injections received. We had only one serious complication (anaphylactoid reaction) and 10 minor complications including headaches (five), pain at injection site (two), dizziness (one), hot flushes (one) and one diabetic patient had different insulin requirements for two days.

Conclusion: Although more research, ideally in the form of a randomised, controlled, double-blind trial is indicated, we have concluded that by either route these injections are a safe and effective measure of temporary pain relief for lumbar radiculopathy and that smoking is associated with higher levels of pain.