Effect of Context Specificity on Response to the Shortened WOMAC Function Scale in Patients Undergoing Total Knee Arthroplasty.

OBJECTIVE: To determine, in patients undergoing total knee arthroplasty (TKA), whether increasing context specificity of selected items of the shortened version of the Western Ontario and McMaster Universities Osteoarthritis Index function (WOMAC-F) scale (ShortMAC-F) (1) enhanced the convergent validity of the ShortMAC-F with performance-based mobility measures (ii) affected mean scale score, structural validity, reliability, and interpretability. DESIGN: Secondary analysis of randomized clinical trial data. SETTING: A tertiary teaching hospital. PARTICIPANTS: Patients undergoing TKA (N=114). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The ShortMAC-F was modified by specifying the "ascending stairs" and "rising from sitting" items to enquire about difficulty in performing the tasks without reliance on compensatory strategies, whereas the modified "level walking" item enquired about difficulty in walking 400 m. Before and 12 weeks after TKA, patients completed the WOMAC-F questionnaire, modified ShortMAC-F questionnaire, knee pain scale questionnaire, sit-to-stand test, fast gait speed test, and stair climb test. Interpretability was evaluated by calculating anchor-based substantial clinical benefit estimates. RESULTS: The modified ShortMAC-F correlated significantly more strongly than ShortMAC-F or WOMAC-F with pooled performance measures (differences in correlation values, 0.12-0.14). Increasing item context specificity of the ShortMAC-F did not influence its psychometric properties of unidimensionality (comparative fit and Tucker-Lewis indices, >0.95; root mean square error of approximation, 0.05-0.08), reliability (Cronbach's α, 0.75-0.83), correlation with pain intensity (correlation values, 0.48-0.52), and substantial clinical benefit estimates (16 percentage points); however, it resulted in lower mean score (4.5-4.8 points lower). CONCLUSIONS: The modified ShortMAC-F showed sufficient measurement properties for clinical application, and it seemed more adept than WOMAC-F at correlating with performance-based measures in TKA.

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.

Adductor Canal Block Does not Confer Better Immediate Postoperative Pain Relief after Total Knee Arthroplasty.

The adductor canal block (ACB) is a useful adjunct to control postoperative pain in total knee arthroplasty (TKA). The aim of our study was to compare postoperative day 1 (POD1) pain scores, ambulation distance, range of motion, active straight leg raise (SLR), and length of stay (LOS) in TKA patients receiving no ACB (NACB), ACB by surgeon (ACBS), or ACB by anesthetist (ACBA). After obtaining institutional ethics approval, a retrospective review of 135 patients who underwent TKA between September 2020 and March 2021 was performed. All patients underwent TKA by the same surgeon and received the same standardized postoperative rehabilitation. Operating theater time was shortest in the NACB group with 129.3 ± 23.1 minutes compared with 152.4 ± 31.6 minutes in ACBA and 139.2 ± 29.4 minutes in ABCS (p = 0.001). For the POD1 pain score after therapy, the NACB group scored 4.9 ± 3.1 compared with 3.5 ± 2.2 and 3.9 ± 1.8 scored by the ACBA and ACBS groups, respectively (p = 0.302). The mean POD1 ambulation distance was 21.1 ± 15.2 m in the NACB group compared with 15.4 ± 1.3 and 17.8 ± 13.2 m in the ACBA and ACBS groups (all p > 0.05), respectively. There were no significant differences in the median LOS between three groups or ability to perform active SLR (all p > 0.05). Our study found no significant differences when comparing ACBS and ACBA by POD1 pain score, ambulation distance, range of motion, and LOS. We recommend against the use of ACB and instead recommend surgeons to perform an adequate periarticular cocktail injection.

Alignment prior to total knee arthroplasty in high tibial osteotomy patients has no effect on subsequent functional outcomes.

INTRODUCTION: The influence of prior high tibial osteotomy (HTO) on total knee arthroplasty (TKA) functional outcomes remains widely debated. Alignment of failed HTO can pose technical challenges with subsequent TKA. The primary aim of this study was to evaluate the influence of HTO alignment on the clinical outcomes of subsequent TKA. The secondary aim was to compare the time to TKA for each HTO alignment type. METHODS: Patients who underwent TKA post lateral closing-wedge HTO for symptomatic medial compartment osteoarthritis between 2001 and 2014 were prospectively followed up for 2 years. A total of 159 patients were assigned to three groups based on their pre-TKA femora tibia angles using long lower limb radiographs: varus alignment (VrA) ≤ 3o valgus, neutral alignment (NA) 3-9o valgus alignment, valgus alignment (VlA) ≥ 9o valgus. Functional outcomes were quantified using Knee Society Function Score and Knee Scores (KSFS and KSKS respectively), modified Oxford Knee Score (OKS), Short Form 36 Physical Component Score (SF-36 PCS), and SF-36 Mental Component Score (SF-36 MCS). Pre-operative and post-operative knee range of motion were also measured. RESULTS: Mean pre-TKA KSKS in VrA patients (35 ± 18) was significantly lower than both NA (51 ± 19) and VlA (40 ± 21) patients (p < .05). Otherwise, there was no significant difference in functional outcome scores (KSFS, KSKS, OKS, SF-36 PCS and SF-36 MCS) or range of motion at 6 months and 2 years post-TKA. The mean duration from HTO to TKA was 12 ± 7 years with no significant differences between VrA, NA, and VlA HTO to TKA (13 ± 7 years, 13 ± 6 years and12 ± 8 years respectively, p > .05). CONCLUSION: HTO alignment did not influence time to subsequent TKA. HTO alignment did not influence early outcomes as well as radiological outcomes of subsequent TKA. LEVEL OF EVIDENCE: III.

No difference in functional outcomes, quality of life and survivorship between metal-backed and all-polyethylene tibial components in unicompartmental knee arthroplasty: a 10-year follow-up study.

PURPOSE: The purpose of this study was to compare functional outcomes, quality of life and survivorship at a minimum of 10 years postoperatively, between MB and AP tibial components in fixed-bearing UKAs. METHODS: A retrospective cohort study of 146 Query ID="Q3" Text="Author names: Please confirm if the author names are presented accurately and in the correct sequence (Lo Ngai Nung, Yeo Seng Jin). Also, kindly confirm the details in the metadata are correct." UKAs performed between 2004 and 2007 by a single fellowship-trained arthroplasty surgeon was carried out. 27 UKAs received MB tibial components and 119 UKAs received AP tibial components. The cohort was followed up prospectively for 10 years. Functional outcomes were compared using the Knee Society Functional Score (KSFS), Knee Society Knee Score (KSKS) and Oxford Knee Score (OKS). Quality of life measures were obtained from the Physical Component Summary (PCS) and Mental Component Summary (MCS), derived from the Short Form 36 Health Survey (SF-36). Propensity score matching was performed in a 1:3 ratio of MB versus AP tibial components to account for possible confounding variables. Thereafter, outcomes between the two groups were compared. The proportion of patients who had attained the minimum clinically important difference (MCID) for the abovementioned scores was recorded as well. RESULTS: After propensity score matching, there were 28 UKAs with MB tibial components and 76 UKAs with AP tibial components. There was no significant difference between the two groups in functional outcomes (KSFS, KSKS and OKS), quality of life (PCS and MCS) and survivorship (92.3% vs 91.1%, respectively) at a minimum of 10 years postoperatively. However, a significantly higher proportion of patients in the group with AP tibial components attained the MCID for PCS at 10 years postoperatively, compared to those with MB tibial components (p = 0.031). CONCLUSION: In conclusion, there were no significant differences in functional outcomes measures, quality of life and survivorship between MP and AP tibial components at a minimum of 10 years postoperatively. LEVEL OF EVIDENCE: III.

Peroneus longus tendon rupture: A case report.

BACKGROUND: Peroneal tendinopathies are an under-diagnosed and potentially under-treated pathology. If left untreated it can be a cause of chronic lateral hindfoot pain. Its diagnosis is challenging owing to its low incidence and vague clinical presentation. CASE SUMMARY: We share a case of a patient who experienced a chronic lateral ankle pain exacerbated after alighting from a bus. This patient came to our attention only after failing conservative management on two separate occasions. Plain radiographs and magnetic resonance imaging revealed rupture of the peroneus longus tendon (PLT). Findings were confirmed intra-operatively and tenodesis of the PLT to the peroneus brevis was performed. Patient was kept non-weight-bear with his foot everted and in plantarflexion before being converted to an off-loading boot at two weeks. Patient was started on a progressive rehabilitation programme at six weeks and was able to return to work shortly after with excellent outcomes. CONCLUSION: We aim to share our experience in managing this patient and propose some pointers guided by available literature to avoid missing this commonly overlooked pathology.