Abstract

Abstract

In light of recent regulatory initiatives, medical devices now require additional clinical evidence to prove their safety and efficacy. At the same time, patients' own assessment of their devices' function and performance has gained in importance. The collection of these data allows for a more comprehensive picture of clinical outcomes and complications following total knee arthroplasty (TKA).

These trends have led researchers to search for new methods of acquiring, interpreting and disseminating patient-reported outcome measurements (PROMs). The current study assesses the feasibility of a digital platform for collecting PROMs that was recently adapted for TKA patients. It sought to determine patient engagement, survey completion rates, and satisfaction with this platform.

Eighty-two patients (mean age, 63.7 years, 59% females) scheduled for TKA were enrolled from one US and six UK sites between January 12, 2018 and April 30, 2018. Patients were supplied with a mobile application (app) that collects a variety of PROMs, including four domains based on the Patient-Reported Outcome Information System (PROMIS™): physical function, depression, pain interference and pain behavior. The platform electronically administers questionnaires using computer-adaptive tests (CATs), which reduce the burden on patients by tailoring follow-up questions to account for their previous answers. Satisfaction with the app was assessed in subset of patients who evaluated its ease-of-use (n=45), likelihood that they would recommend it to family/friends (n=35), and whether they successfully used the information it provided during their recovery (n=31). These scores were taken on a 1 to 10 (worst to best) scale.

Patients demonstrated regular engagement with the platform, with 73% using the app at least once a week. Weekly engagement remained high throughout the seven-week post-operative period (Figure 1). There was a 69% completion rate of all PROMIS™ CAT surveys during the study. The four PROMIS™ CAT domains had similar survey completion rates (Figure 2). The subset of patients queried regarding their satisfaction with the app gave it favorable mean scores for ease-of-use (8.8), likelihood to recommend to a family member or friend (8.1), and their success at using its information to improve their recovery (7.4).

Initial results support this digital platform's potential for successfully and efficiently collecting large volumes of PROMs. Patients reported high levels of engagement and satisfaction.

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The quality of bone in the skeleton depends on the amount of bone, geometry, microarchitecture and material properties, and the molecular and cellular regulation of bone turnover and repair. This study aimed to identify material and structural factors that alter in fragility hip fracture patients treated with antiresorption therapies (FxAr) compared to fragility hip fracture patients not on treatment (Fx).

Bone from the intertrochanteric site, femoral head (FH: FxAr = 5, Fx = 8), compression screw cores and box chisel were obtained from patients undergoing hemi-arthroplasty surgery, FxAr (6f, 2m, mean 79 and range [64–89] years), and Fx (7f, 1m, age 85 [75–93] years). Control bone was obtained at autopsy (9f, 4m, 77 [65–88] years). Treated patients were on various bisphosphonates. Samples were resin-embedded, for quantitative backscattered electron imaging of the degree of mineralisation and assessment of bone architecture. Trabecular bone volume fraction (BV/TV) and architectural parameters were not significantly different between FxAr and Fx groups.

Both groups showed normal distributions of weight (wt) % Ca; however, the FxAr was less mineralised than the Fx and the control group (mean wt % Ca: FxAr = 24.3%, Fx = 24.8%, Control = 24.9%). When comparing the FH specimens only, we found that BV/TV in the FxAr was greater than the Fx group (18% vs 15%). All other parameters were not significantly different. In addition, the mineralisation was greater in the FxAr group compared to the Fx group (25.5 % vs 25.0%) but was not significantly different.

Collectively, these data suggest the effect on bone of antiresorptives may be different for patients on antiresorptive treatment that do not subsequently fracture. Assessment of bone material property data together with other bone quality measures may hold the key to better understanding of antiresorptive treatment efficacy.

The low contact stress patellofemoral replacement consists of a trochlear component and a modular patellar component which has a metal-backed mobile polyethylene bearing. We present the early results of the use of this prosthesis for established isolated patellofemoral arthritis in 51 consecutive patellofemoral replacements in 35 patients. The mean follow-up was 25 months (5 to 60). The estimated survival rate at three years was 63% (95% confidence interval 47 to 80) with revision as the endpoint and 46% (95% confidence interval 30 to 63) with revision and ongoing moderate or severe pain as the endpoint.

The early results of the use of the low contact stress patellofemoral replacement are disappointing with a high rate of revision. We cannot therefore recommend its use.

We report our experience with LCS Patellofemoral joint replacement. Between September 2003 and November 2007, 66 consecutive patients were reviewed retrospectively who underwent LCS patellofemoral joint replacement. There were 13 males and 51 females with a mean age of 61.6 years (range 43–78). The average follow-up was 22 months (range 11–51 months). To assess the outcome, revision for any cause was taken as the end point for this study.

A total of 14 (21.2%) revision operations were carried out at an average of 15.6 months (range 8–29 months) from the initial operation. The reasons for revision were mal-tracking of patella (3), dislocated patellar button (2), persistent unexplained pain (5) and progression of arthritis (4). Amongst the remaining 52 patients, 8 are still experiencing pain and not entirely satisfied with the procedure. 42 patients (63%) have a satisfactory outcome so far. All of them who underwent revision to a total knee replacement were satisfied with their outcome with relief in their symptoms. Revision to a total knee replacement is not a straightforward procedure, especially removing the metal backed patellar component.

The revision rate of over 21% is unacceptably high to recommend the procedure as a routine. Based on our experience, we conclude that LCS patellofemoral replacement should be used with caution.

Evidence is accumulating for the role of bone in the pathogenesis of osteoarthritis (OA). Previous studies have shown a generalised increase in bone mass and hypo-mineralisation in OA patients. However, the molecular and cellular mechanisms involved in the increased bone mass and matrix compositional profiles in OA, at distal skeletal sites to the articular cartilage, have not yet been well defined. This study examined whether gene expression of bone anabolic factors, trabecular bone architecture and matrix mineralisation are altered in human OA and non-OA hipbone. Intertrochanteric (IT) trabecular bone samples were obtained from 15 primary hip OA patients (mean age 65 [48–85] years) and 13 closely age- and gender-matched autopsy controls (mean age 63 [44–83] years). Semi-quantitative RT-PCR analysis revealed elevated mRNA expression levels of alkaline phosphatase (p < 0.002), osteocalcin (p < 0.0001), osteopontin (p < 0.05), collagen type-I α chains COL1A1 (p < 0.0001) and COL1A2 (p < 0.002), in OA bone compared to control, suggesting possible increases in osteoblastic biosynthetic activity and/or bone turnover at the IT region in OA. Interestingly, the ratio of COL1A1:COL1A2 mRNA was almost 2-fold greater in OA bone compared to control (p < 0.001), suggesting the potential presence of collagen type-I homotrimer at the distal site that may associate with hypomineralisation in OA individuals. Using a quantitative backscatter electron imaging technique, mineralisation profiles of IT trabecular bone indicated decreased mineralisation in the OA group compared to the control group (24.2 weight percent calcium [wt%Ca] versus 25.3 wt%Ca). Bone histomorphometric analysis found OA IT bone had increased surface density of bone and decreased trabecular separation compared to control bone. Taken together with a reported increase in diffuse microdamage in OA IT bone (Fazzalari et al. Bone 31:697–702, 2002), possibly due to hypomineralisation, these results are consistent with the altered bone material properties found in OA individuals. The finding of differential gene expression, altered mineralisation and architectural changes in OA bone, at a skeletal site distal to the active site of joint degeneration, supports the concept of systemic involvement of bone in the pathogenesis of OA.

Radial cleavage tears of the lateral meniscus are uncommon and may be associated with a meniscal cyst. There is a recognised association of these lesions with radiographically visible erosions of the lateral tibial plateau; however, this association is reported to be rare. We believe this radiographic feature is more common than previously reported and as most reports are limited to the radiology literature it is not widely appreciated by Orthopaedic Surgeons. The aim of this study was to determine the prevalence of this valuable radiographic sign in patients with a proven radial cleavage tear and draw attention to it among Orthopaedic Surgeons.

We identified 20 patients from our prospectively collected database that had undergone an arthroscopic partial lateral meniscectomies for radial cleavage tears of the lateral menisci. A consultant radiologist (NS) independently assessed the pre-operative radiographs of these patients, specifically looking for the presence of erosions of the tibiae below the lateral joint line. Of 20 patients assessed 9(45%) had radiographically visible bone erosions.

Our study confirms our clinical experience that patients with symptoms and signs suggestive of a radial cleavage tear of the lateral meniscus frequently have an associated plain radiographic sign to support the clinical diagnosis.

Aim: To estimate the prevalence of iron deficiency in patients undergoing primary total hip (THR) or knee (TKR) replacement surgery and to test the clinical effectiveness of routinely prescribing iron supplements to all anæmic patients after THR and TKR.

Method: This was designed as a randomised, doubleblind, placebo-controlled trial. Serum ferritin was measured in 230 consecutive patients admitted for primary THR or TKR. Seventy-two patients were entered into the randomised arm of the trial, 35 were randomised to the treatment group, and 37 to the placebo group. Patients meeting the inclusion criteria after primary THR or TKR were randomised to receive six week’s treatment with either ferrous sulphate (200mg) or an identical gelatin placebo, three times daily. The serum ferritin level and the change in hæmoglobin were measured between five and seven days post-operatively and each patient attended for an out-patient review at six weeks after the surgery.

Results: The study achieved a statistical power of 80%. Serum ferritin was abnormally low in 15 of 230 patients (6.5%). Hæmoglobin in the group of patients receiving ferrous sulphate increased by a mean of 0.31 g/dL more than the group receiving the placebo (95% confidence interval −0.17 −0.79 g/dL). This difference was not statistically significant (p=0.18).

Conclusions: We found that iron deficiency was uncommon in patients who had undergone primary THR or TKR. The routine prescription of oral iron salts to all anæmic patients after these procedures had no clinical benefit.