Bone-on-Bone Contact on Radiograph is not a Prerequisite for Successful Outcome in Fixed-Bearing Medial Unicompartmental Knee Arthroplasty—A 10-Year Follow-Up Study

Introduction Patients without bone-on-bone osteoarthritis are excluded from mobile-bearing unicompartmental knee arthroplasty due to higher revision rates and poorer outcomes. However, we do not know if the same indication applies to fixed-bearing unicompartmental knee arthroplasty implants. Our study aims to compare functional outcomes and revision rates in patients with and without bone-on-bone arthritis undergoing fixed-bearing medial unicompartmental knee arthroplasty. Materials and Methods We reviewed 153 fixed-bearing medial unicompartmental knee arthroplasties in a single institution. Patients were divided into four groups based on joint space remaining measured on preoperative radiographs. Group 1 included knees with bone-on-bone contact; group 2 included knees with less than 2 mm joint space; group 3 included knees with 2 to 4 mm joint space; group 4 included knees with more than 4 mm joint space. Patients were followed up for 10 years postoperatively and assessed using the Oxford Knee Score, the Functional Score and Knee Score from the Knee Society Clinical Rating Score, and the Short Form 36 Health Survey. Results There was no difference in terms of demographic data and preoperative scores. Postoperative Knee Society Functional Score was found to be lower in group 1 as compared with the other groups. There was no difference between the four groups of patients in terms of Knee Society Knee Score, Oxford Knee Score, and Physical Component Summary and Mental Component Summary Scores from the Short Form 36 Health Survey. There was no difference in terms of survivorship free from all-cause revision at a minimum of 10 years' follow-up. Conclusion Symptomatic patients with varying degrees of arthritis on preoperative radiographs had comparable clinical outcomes. We conclude that symptomatic patients with clinical and radiographic evidence of medial compartment osteoarthritis of any grade can benefit from a fixed-bearing medial unicompartmental knee arthroplasty.

Recovery patterns in patients undergoing revision surgery of the primary knee prosthesis

Purpose Despite good survival rates of revised knee prostheses, little is known about recovery trajectories within the first 12 months after surgery. This retrospective observational study explored recovery trajectories in terms of pain, function and quality of life in patients after revision knee arthroplasty over 12 months. Methods Eighty-eight revision knee arthroplasty patients rated changes in daily physical functioning using the anchor question (0: very much worsened; 7: very much improved). Patient reported outcome measures (PROMs) of pain (range 0–10), function (Oxford Knee Score) and quality of life (EQ-5D-3L) were assessed preoperatively, at 3 and 12 months postoperatively. Four recovery trajectories were identified using the anchor question at 3 and 12 months postoperatively: no improvement, late improvement, early improvement, and prolonged improvement. Repeated measures ANOVA was conducted with recovery trajectories as dependent variable and PROM assessments as independent variables. Results Sixty percent reported improvement in daily physical functioning at 12 months postoperatively. Age and reason for revision differed between groups. Pain, function and EQ-5D-3L differed between groups over time. Late and prolonged improvement groups improved on all PROMs at 12 months. The early improvement group did not report improvement in daily physical functioning at 12 months, while improvements in function and pain during activity were observed. Conclusions Different recovery trajectories seem to exist and mostly match PROMs scores over time. Not all patients may experience beneficial outcome of revision knee arthroplasty. These findings are of importance to provide appropriate information on possible recovery trajectories after revision knee arthroplasty to patients. Level of evidence III

A matched comparison of the patient-reported outcome measures of cemented and cementless total knee replacements, based on the National Joint Registry of England, Wales, Northern Ireland, and Isle of Man and England’s National PROM collection programme

Background and purpose — Total knee replacement (TKR) can be implanted with or without bone cement. It is currently unknown how the functional outcomes compare. Therefore, we compared the patient-reported outcome measures (PROMS) of both fixation methods. Patients and methods — We performed a propensitymatched comparison of 14,404 TKRs (7,202 cemented and 7,202 cementless) enrolled in the National Joint Registry and the English National PROMs collection programme. Subgroup analyses were performed in different age groups (1) < 55 years; (2) 55–64 years; (3) 65–74 years; (4) ≥ 75 years. Results — The 6-month postoperative Oxford Knee Score (OKS) was significantly (p < 0.001) higher for cemented TKR (35, SD 9.7) than cementless TKR (34, SD 9.9). The OKS was also significantly higher for the cemented TKR in all age groups, except the 55–64-year group. A significantly higher proportion of cemented TKRs had an excellent OKS (≥ 41) compared with cementless (32% vs. 28%, p < 0.001) and a lower proportion of poor (< 27) scores (19% vs. 22%, p = 0.001). This was also observed for all age subgroups. Therewere no significant differences in EQ-5D points gained postoperatively between the groups respectively (0.31 vs. 0.30, p = 0.1). Interpretation — Cemented TKRs had a greater proportion of excellent OKS scores and lower proportion of poor scores both overall and across all age groups. However, the absolute differences are small and below the minimally clinically important difference, making both fixation types acceptable. Currently the vast majority of TKRs are cemented and the results from this study suggest that this isappropriate.

Comparison of the Functional and Radiological Outcomes of Single- and Two-Stage Bilateral Open Wedge High Tibial Osteotomy

Purpose This study compared the functional and radiological outcomes and complications of single- (SS) and two-stage (TS) bilateral high tibial osteotomy (HTO). Methods From 2014 to 2018, 48 patients underwent bilateral HTO surgery for osteoarthritis. The outcomes of SS in 28 knees and TS in 32 knees were compared using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and Oxford Knee Score (OKS) as functional outcomes, and the medial proximal tibial (MPTA), hip-knee-ankle (HKA), tibial slope (TSA) angles, and mechanical axis deviation (MAD) as radiological outcomes. We also evaluated the estimated blood loss (EBL). Results No significant differences in the pre- and postoperative mean OKS and KOOS were found between the groups. There was a significant difference between the groups in the last postoperative HKA angle (− 0.9 ± 3.9 and 1.8 ± 4.3°, respectively). In SS and TS, the respective total mean surgical time was 108 ± 28 and 143 ± 36 min (p < 0.001). The mean calculated EBL was 612 ± 267 and 544 ± 357 mL, respectively, (p = 0.5), and the mean length of stay (LOS) was 2.2 ± 0.83 and 3.5 ± 1.0 days, respectively, (p = 0.01). Conclusion SS bilateral HTO is a safe reasonable option for certain patients with bilateral knee osteoarthritis because it involves a single hospitalization, one-time exposure to anesthesia risks, accelerated rehabilitation, earlier return to expected life status, reduced total hospital stay, and a likely decrease in total cost.

Bi-unicondylar arthroplasty

Aims Bi-unicondylar arthroplasty (Bi-UKA) is a bone and anterior cruciate ligament (ACL)-preserving alternative to total knee arthroplasty (TKA) when the patellofemoral joint is preserved. The aim of this study is to investigate the clinical outcomes and biomechanics of Bi-UKA. Methods Bi-UKA subjects (n = 22) were measured on an instrumented treadmill, using standard gait metrics, at top walking speeds. Age-, sex-, and BMI-matched healthy (n = 24) and primary TKA (n = 22) subjects formed control groups. TKA subjects with preoperative patellofemoral or tricompartmental arthritis or ACL dysfunction were excluded. The Oxford Knee Score (OKS) and EuroQol five-dimension questionnaire (EQ-5D) were compared. Bi-UKA, then TKA, were performed on eight fresh frozen cadaveric knees, to investigate knee extensor efficiency under controlled laboratory conditions, using a repeated measures study design. Results Bi-UKA walked 20% faster than TKA (Bi-UKA mean top walking speed 6.7 km/h (SD 0.9),TKA 5.6 km/h (SD 0.7), p < 0.001), exhibiting nearer-normal vertical ground reaction forces in maximum weight acceptance and mid-stance, with longer step and stride lengths compared to TKA (p < 0.048). Bi-UKA subjects reported higher OKS (p = 0.004) and EQ-5D (p < 0.001). In vitro, Bi-UKA generated the same extensor moment as native knees at low flexion angles, while reduced extensor moment was measured following TKA (p < 0.003). Conversely, at higher flexion angles, the extensor moment of TKA was normal. Over the full range, the extensor mechanism was more efficient following Bi-UKA than TKA (p < 0.028). Conclusion Bi-UKA had more normal gait characteristics and improved patient-reported outcomes, compared to matched TKA subjects. This can, in part, be explained by differences in extensor efficiency. Cite this article: Bone Joint Res 2021;10(11):723–733.

Non-inferiority of The Cementless Total TKA Compared to The Cemented TKA, A m-Metanalysis

Objective: Cemented total knee arthroplasty still represents the reference standard in the field of prothesis knee replacement; but since cementless total knee arthroplasties were introduced there have been strong discussions over the years among cemented and non-cemented total knee arthroplasties to establish which gives the best benefits for the patient and for the surgeon. The purpose of this meta-analysis is to systematically analyze the use of cemented and cementless total knee arthroplasties by investigating clinical and radiological outcomes and rate of complications, in order to assess which techniques confers more benefits to the patient and the surgeon. Materials and Methods: The current systematic review has been written in accordance to the Cochrane handbook and the PRISMA statement for reporting of systematic reviews incorporating network. Results: Six randomized controlled trials were finally included in this systematic review. The statistical analysis revealed no significant differences in all clinical scores of interest (Knee Society Score, clinical and functional, Oxford Knee Score, Visual Analogue Score) and a similar revision rate. Conclusion: the results of the current metanalysis suggest the non-inferiority of cementless fixation with respect to cemented total knee arthroplasties in terms of clinical outcomes and survival rates of the implants.

A randomized controlled trial comparing functional outcomes for navigated kinematically aligned total knee arthroplasty versus navigated mechanically aligned total knee arthroplasty

Aims Nearly 99,000 total knee arthroplasties (TKAs) are performed in UK annually. Despite plenty of research, the satisfaction rate of this surgery is around 80%. One of the important intraoperative factors affecting the outcome is alignment. The relationship between joint obliquity and functional outcomes is not well understood. Therefore, a study is required to investigate and compare the effects of two types of alignment (mechanical and kinematic) on functional outcomes and range of motion. Methods The aim of the study is to compare navigated kinematically aligned TKAs (KA TKAs) with navigated mechanically aligned TKA (MA TKA) in terms of function and ROM. We aim to recruit a total of 96 patients in the trial. The patients will be recruited from clinics of various consultants working in the trust after screening them for eligibility criteria and obtaining their informed consent to participate in this study. Randomization will be done prior to surgery by a software. The primary outcome measure will be the Knee injury and Osteoarthritis Outcome Score The secondary outcome measures include Oxford Knee Score, ROM, EuroQol five-dimension questionnaire, EuroQol visual analogue scale, 12-Item Short-Form Health Survey (SF-12), and Forgotten Joint Score. The scores will be calculated preoperatively and then at six weeks, six months, and one year after surgery. The scores will undergo a statistical analysis. Discussion There is no clear evidence on the best alignment for a knee arthroplasty. This randomized controlled trial will test the null hypothesis that navigated KA TKAs do not perform better than navigated MA TKAs. Cite this article: Bone Jt Open 2021;2(11):945–950.

A study on functional outcome of posterior cruciate ligament substituted total knee arthroplasty

<p class="abstract"><strong>Background: </strong>Total knee replacement surgery is considered as a treatment of choice in patients with advanced arthritis, especially in patients where conservative treatment has been failed. Total knee replacement gives good pain relief, functional improvement of knee and correction of deformity.</p><p class="abstract"><strong>Methods:</strong> This is study of 39 patients following total knee arthroplasty, who were operated between August 2017 and March 2020 at MNR Medical College and Hospital, Sangareddy. They were followed up for a minimum period of 1 year and evaluated using oxford knee scoring system. Oxford knee score is designed specifically for measuring outcomes in knee arthroplasty. There were 14 right knees, 10 left knees, 15 bilateral knees.</p><p class="abstract"><strong>Results: </strong>There was a significant functional improvement of knee in patients and we had achieved excellent results, out of 39 patients and 4 patients had post op suprapatellar fullness, which was relieved with medications for 3 weeks and 2 patients (2 knees) without no signs of immediate post-operative period, developed infection after 6 months followed which underwent staged revision total knee replacement. The outcome categories based on oxford knee scoring system: excellent (40-48), good (30-39), fair (20-29) and poor (0-19).</p><p class="abstract"><strong>Conclusions: </strong>It is difficult to balance the knee with retention of posterior cruciate ligament, whereas posterior cruciate ligament substituting total knee replacement gives reproducible and good results, hence it is the preferred mode of management.</p>