BACKGROUND

Since 1996, the Scottish Hip Fracture Audit (SHFA) group have published reports on the outcomes of patients with hip fractures. In the 2008 report, the group outlined the target standard that “98% of medically fit patients who have sustained a hip fracture should be operated on within 24 hours of ‘safe operating time’ (i.e. between 8 am and 8pm, seven days a week).”¹.

Patient reported outcome measures (PROMs) are important for assessing the results of lower limb arthroplasty. Unrealistic or uneducated expectations may have a significant negative impact on PROMs even when surgery is technically successful. This study's aim was to quantify pre-operative expectations of Scottish patients undergoing total hip and knee replacement (THR/TKR).

100 THR and 100 TKR patients completed validated questionnaires (from the Hospital for Special Surgery) prior to their operation after receiving standard pre-operative information (booklet, DVD, consultations). Each patient rated expectations from very important to not having the expectation. A total score was calculated using a numerical scale for the grading of each expectation. Univariate regression analysis was used to investigate the relationship between demographics and expectation score.

The THR cohort had mean age 66.2 (SD 10.5), 53% female, mean BMI 29.0 (SD 5.1) and mean Oxford score 44 (SD 7). The TKR cohort had mean age 67.6 (SD 8.5), 59% female, mean BMI 32.8 (SD 5.8) and mean Oxford score 44 (SD 8). 100% THR and 96% TKR patients had 10 or more expectations of their operation. All expected pain relief. Other improvements expected were: walking for 100% THA and 99% TKA patients; daily activities for 100% THAs and 96% TKAs; recreational activities for 96% THAs and 93% TKAs; sexual activity for 66% THAs and 59% TKAs; psychological well-being for 98% THAs and 91% TKAs. Regression analysis showed increasing age lowered expectations in both THR (p=0.025) and TKR (p=0.031) patients but that gender, BMI and Oxford score were not significantly related to expectations.

This study highlights that patients expect far more than pain relief and improved post-operative mobility from their operation. It is important to discuss and manage these expectations with patients prior to surgery. By doing so, patient satisfaction and PROMs should further improve.

Recent debate about changing population demographics and growing demands of younger patients has suggested a future explosion in the requirements for primary and revision lower limb arthroplasty (TKA/THA). This could represent a significant challenge for healthcare providers. This study aimed to predict the demands for lower limb arthroplasty in Scotland from 2010–2035.

Population figures (2004–2010) and projected population data (five year increments) were obtained from the National Records of Scotland. The numbers of arthroplasties from 2004–2010 were provided by the Scottish Arthroplasty Project. Data were divided into three age groups (40–69, 60–79, 80+). The first model used mean incidence for each age group from 2006–2010 applied to the projected population figures. The second used linear regression to give predicted incidences 2015–2035 which were then applied to the projected population. The third-for revisions – used incidence per number of primary arthroplasties.

For primary TKA model 1, comparing to 2010, showed demand increasing by 10% in 2020 and by 31% (to 8,650 procedures) in 2035. Model 2 gave increases of 60% and 161% respectively. An increase was found across all age groups with 60–79 more than doubling and 80+ increasing fourfold by 2035 (model 2). The revision TKA models predicted between 670 and 2,000 procedures by 2035. For primary THA models 1 and 2 showed demand increasing by 40% in 2020 and then by 60% and 110% (11,000 and 14,500 procedures) in 2035 respectively. All age groups had increasing demand with 60–79 doubling and 80+ tripling by 2035 (model 2). The revision THA models predicted between 1,300 and 2,100 procedures by 2035.

These projections show large increases in the numbers of both primaries and revisions over the next two decades. They highlight that current resources may be insufficient or the selection criteria for surgery may need to be revisited.

Component malrotation in total knee arthroplasty (TKA) is a reason for early failure and revision. Assessment of possible component malrotation using computed tomography (CT) might be useful when other differentials have been excluded. The aims of our study were to determine the proportion of symptomatic patients with component malrotation on CT, and review the subsequent management of such patients.

A retrospective review of case notes was performed locally for all patients who had a CT scan for a painful TKA. Measurements of the femoral and tibial component rotations were done according to the standard Berger protocol, giving net degrees of either external rotation (ER) or internal rotation (IR). Any subsequent surgery was noted, and patients were followed up as per local practice.

Between 2007 and April 2012, 69 knees in 68 patients had CT scans. There were 25 males and 43 females, and mean age at primary surgery was 65.03 years. The mean femoral component rotation for all knees was 0.1° ER (range 7.0° ER – 6.7° IR), and the mean tibial component rotation for all knees was 19.1° IR (6.6° ER – 37.0° IR). No statistically significant difference was found comparing the mean femoral and tibial component rotations between patients with and without further surgery. Further surgery was performed on 39 (56.5%) knees.

Overall, there were ten cases (14.5%) of isolated femoral malrotation, 26 tibial malrotation (37.7%), and two cases (2.9%) had malrotation of both components. Out of these 38 cases, secondary surgery was performed in 22 knees (57.9%), of which a satisfactory outcome was achieved in fifteen cases (68.1%).

It is impossible to establish component malrotation as the only cause of pain following TKA, however, our study does show that the Berger protocol has its uses when other causes have been excluded.

The role of digital radiography has evolved in recent years. In many hospitals, radiographs have been completely digitised and moved to Picture Archiving and Communications System (PACS). Pre-operative templating for arthroplasty has been a major problem as a result.

We investigate the accuracy of Orthoview™ software in templating for hip and knee arthroplasty. A retrospective review of 20 Stryker-Exter hip and 20 Biomet-Vanguard knee arthroplasties was conducted. Anonymised preoperative radiographs were reviewed by experienced orthopaedic surgeons. Templated component sizes were compared with actual implanted component sizes. All radiographs were digitised on Kodak Carestream PACS. Five surgeons were asked to separately review the radiographs to avoid intra-observer error.

In templating for hip arthroplasty, Orthoview™ was 80% accurate in predicting the femoral stem size within one size of the actual component used. It predicted the offset with 100% accuracy. In 90% of patients, the actual head implant was within one size of the templated head. The system was able to predict the acetabular component size in only 30%. In knee arthroplasty, Orthoview™ was 80% accurate within one size of the actual component used for the femur and 90% for the tibia.

Orthoview™ enables the flexibility of digitised films to be used for pre-operative templating. It is reasonably accurate in prediction of femoral sizing in both hip and knee arthroplasty and tibial size in knee arthroplasty. It is considerably less useful for acetabular sizing. Surgeons should keep this variability in mind until more accurate systems are available.