Total Knee Arthroplasty After High Tibial Osteotomy Results in Excellent Long-Term Survivorship and Clinical Outcomes

Nearly 14-Fold Increased Risk of Manipulation Under Anesthesia After Total Knee Arthroplasty When Previous Contralateral Total Knee Arthroplasty Required Manipulation Under Anesthesia

BACKGROUND

Stiffness remains a common complication after primary total knee arthroplasty (TKA). Manipulation under anesthesia (MUA) is the gold standard treatment for early postoperative stiffness; however, there remains a paucity of data on the risk of MUA after primary TKA if a prior contralateral TKA required MUA.

METHODS

We performed a retrospective review of 3,102 patients who had staged primary TKAs between 2016 and 2021. The mean body mass index was 33 (range, 18 to 59) and the mean age was 67 years (range, 24 to 91). The mean preoperative range of motion for the first TKA was 2 to 104°, and for the contralateral TKA was 1 to 107°. The primary outcomes were MUA following first and second primary TKAs. Multivariable Poisson regressions were used to evaluate associations between risk factors and outcomes.

RESULTS

The rate of MUA after the first TKA was 2.6% (n = 83 of 3,102) and 1.3% (n = 40 of 3,102) after the contralateral TKA. After adjustment, there was a nearly 14-fold higher rate of MUA after the second TKA if the patient had an MUA after the first TKA (relative risk, 13.80; 95% CI [confidence interval], 7.14 to 26.66). For the first TKA, increasing age (adjusted risk ratio [ARR], 0.65; 95% CI, 0.50 to 0.83) and increasing body mass index (ARR, 0.65; 95% CI, 0.47 to 0.90) were associated with lower risk for MUA. For the second TKA, increasing age was associated with a lower risk of MUA (ARR, 0.60; 95% CI, 0.45 to 0.80).

CONCLUSIONS

For patients undergoing staged bilateral TKA, patients who undergo MUA following the first primary TKA are nearly 14-fold more likely to undergo an MUA following the contralateral primary TKA than those who did not have an MUA after their first TKA.

No clinical outcome difference between varus phenotypes after medial opening-wedge high tibial osteotomy at 2 years follow-up

PURPOSE

Clinical studies regarding medial open-wedge high tibial osteotomy (MOWHTO) often analyse a large group of mechanical varus knees rather than differentiating for its primary varus-inducing component. This study aims to compare the radiological and clinical outcomes of the most prevalent varus malalignment phenotypes using the coronal plane alignment of the knee (CPAK) classification.

METHODS

MOWHTO cases with minimal 2-year clinical follow-up were retrospectively selected from a knee osteotomy database (2016-2020). Based on the medial proximal tibial angle (MPTA) and lateral distal femoral angle (LDFA), subjects were allocated to the correct CPAK phenotype pre- and postoperatively. Clinical outcomes were the numeric rating scale (NRS), the knee injury and osteoarthritis outcome score (KOOS) and the therapeutic response rate (TRR) at 2-year follow-up. Inter-observer correlation coefficient (ICC) and unpaired student t test were performed for cross-phenotype comparison.

RESULTS

One hundred thirty-five (135) subjects were found eligible (53.0 years old ±9.6 [19-77], 72% male, 53% left-sided). The most prevalent preoperative phenotype was CPAK 1 (n = 70 (52%)) and the postoperative phenotype was CPAK 6 (n = 66 (49%)). All CPAK phenotypes improved significantly relative to baseline but cross-phenotype comparison yielded no significant differences in clinical outcome. The TRR at 2 years was 67% for CPAK 1, 69% for CPAK 2 and 87% for CPAK 4. The TRR for CPAK 6 was 64% compared with 80% for CPAK 9, which was not significantly different.

CONCLUSION

At 2-year follow-up, no clinically significant differences are observed between different CPAK phenotypes. Accurate MOWHTO corrections provide significant clinical improvement even in the femoral-driven varus knee and the constitutional varus knee dominated by intra-articular wear. The clinical indication for MOWHTO performance should not be reduced to the medial arthritic varus knee with underlying tibial varus alone.

LEVEL OF EVIDENCE

Level IV, retrospective comparative study.

High survivorship rate and good clinical outcomes after high tibial osteotomy in patients with radiological advanced medial knee osteoarthritis: a systematic review

INTRODUCTION

The role of valgus producing high tibial osteotomy (HTO) for the treatment of advanced knee osteoarthritis (OA) is still controversial. The aim of the current systematic review was to assess survivorship and patient-reported outcomes (PROMs) of high tibial osteotomy in patients with radiological advanced medial knee OA.

METHODS

A systematic search of PubMed, Cochrane and EMBASE database was performed in July 2023 in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines. Inclusion and exclusion criteria were applied to identify studies investigating the survivorship rate and PROMs of valgus-producing high tibial osteotomy in patients with advanced knee OA at x-ray assessment in the medial compartment at minimum-two-years follow up. Advanced radiological OA was defined as Kellgren Lawrence (K-L) ≥ 3 or Ahlbäch ≥ 2. Survivorship was defined as percentage of patients free of total knee arthroplasty (TKA) at follow-up. Clinical interpretation of provided PROMs were performed according to minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) target values reported in literature. Survivorship data and PROMs scores were extracted, and studies were stratified based on selected study features. The quality of included studies was assessed with modified Coleman score.

RESULTS

A total of 18 studies, totalling 1296 knees with a mean age between 46.9 and 67 years old, were included. Average survivorship was of 74.6% (range 60 - 98.1%) at 10-years follow up. The subjective scoring systems showed good results according to MCID and PASS, and postoperative improvements were partially maintained until final follow-up.

CONCLUSION

HTO is worth considering as treatment choice even in patients affected by radiological advanced medial knee osteoarthritis. Long term survivorship and good patient reported clinical outcomes could be expected in this population.

LEVEL OF EVIDENCE

IV; systematic review of level III-IV studies.

Obesity does not impact complications and conversion to total knee arthroplasty after high tibial osteotomy: A systematic review

PURPOSE

The purpose of this systematic review is to consolidate outcomes of obese patients undergoing high tibial osteotomy and to investigate the effect of obesity on postoperative outcomes, including symptomatic relief and time to conversion to arthroplasty.

METHODS

Medline, Embase and Cochrane Library were searched from database inception up to April 2023 according to PRISMA guidelines by two reviewers. Search terms including 'obesity', 'BMI', 'osteotomy' and 'high tibial osteotomy (HTO)' were included to identify all relevant articles. Only studies that explicitly reported outcomes for obese patients were included. Disagreements in study inclusion or quality assessment were resolved by a senior third reviewer. Metrics compared include time to arthroplasty, preoperative and postoperative mechanical tibiofemoral angle (mTFA), patient-reported satisfaction scores and postoperative complications.

RESULTS

Nine studies comparing 973 patients were included. The mean age was 52.7 ± 4.2 years old and 38.4% were male. Six studies performed the medial opening-wedge HTO, and three utilized the medial wedge closing technique. Most studies indicated significant improvement following surgical intervention with satisfactory outcomes in obese and nonobese patients. In addition, differences in complication rates were minimal between obese and nonobese patients (n.s.), while functional scores did not vary significantly. Conversion to total knee arthroplasty was not found to increase in obese patients (n.s.).

CONCLUSION

Obesity does not appear to carry a greater complication risk or worse outcomes following high tibial osteotomies, and surgeons should consider HTO a viable option for young obese patients with symptomatic unicompartmental chondral wear with coronal limb malalignment.

LEVEL OF EVIDENCE

Level IV.

Global mapping of institutional and hospital-based (Level II-IV) arthroplasty registries: a scoping review

PURPOSE

Four joint arthroplasty registries (JARs) levels exist based on the recorded data type. Level I JARs are national registries that record primary data. Hospital or institutional JARs (Level II-IV) document further data (patient-reported outcomes, demographic, radiographic). A worldwide list of Level II-IV JARs must be created to effectively assess and categorize these data.

METHODS

Our study is a systematic scoping review that followed the PRISMA guidelines and included 648 studies. Based on their publications, the study aimed to map the existing Level II-IV JARs worldwide. The secondary aim was to record their lifetime, publications' number and frequency and recognise differences with national JARs.

RESULTS

One hundred five Level II-IV JARs were identified. Forty-eight hospital-based, 45 institutional, and 12 regional JARs. Fifty JARs were found in America, 39 in Europe, nine in Asia, six in Oceania and one in Africa. They have published 485 cohorts, 91 case-series, 49 case-control, nine cross-sectional studies, eight registry protocols and six randomized trials. Most cohort studies were retrospective. Twenty-three per cent of papers studied patient-reported outcomes, 21.45% surgical complications, 13.73% postoperative clinical and 5.25% radiographic outcomes, and 11.88% were survival analyses. Forty-four JARs have published only one paper. Level I JARs primarily publish implant revision risk annual reports, while Level IV JARs collect comprehensive data to conduct retrospective cohort studies.

CONCLUSIONS

This is the first study mapping all Level II-IV JARs worldwide. Most JARs are found in Europe and America, reporting on retrospective cohorts, but only a few report on studies systematically.

Bilateral Inverted V-shaped High Tibial Osteotomy: A Case Report

The article describes the case of a young patient with bilateral genu varum deformity, limiting her mobility. The therapeutic decision was a staged reverse V-shaped tibial osteotomy on both knees at a six-month interval. The surgery faced infectious complications on the left side, requiring additional treatment. Despite this, the patient achieved successful correction, with wound healing and bone consolidation. Preoperative planning was crucial, determining specific correction angles for each knee. The reverse V-shaped osteotomy demonstrated satisfactory functional outcomes compared to other techniques. The conclusion emphasizes the effectiveness of reverse V-shaped high tibial osteotomy (HTO) in addressing varus tibial deformities, providing an alternative before considering total knee arthroplasty. Multicenter studies and long-term evaluations are recommended to refine this surgical procedure.

Staged Extra-Articular Deformity Correction in the Setting of Total Knee Arthroplasty

Background

Extra-articular lower-leg deformities mandate unique considerations when planning total knee arthroplasty (TKA). Poor limb alignment may increase perioperative complications and cause early implant failure. This study reports on the safety and efficacy of staged, extra-articular deformity correction about the knee in the setting of osteoarthritis and TKA.

Methods

A retrospective review was conducted from December 2007 to December 2019 identifying 30 deformities in 27 patients (average age: 52.7 years; range 31-74) who underwent staged surgical correction of extra-articular deformity in preparation for TKA. Patient demographics, surgical details, clinical and radiographic measurements, severity of knee arthritis, and complications were collected.

Results

There were 17 femur and 12 tibia deformities. There was an average improvement of 14.7° of deformity measured in the coronal plane and 12.7° of deformity in the sagittal plane in the femur and 13.5° in the coronal plane and 10.3° in the sagittal plane in the tibia. Leg length discrepancies improved by 26 mm on average (1-100 mm). After an average 3.1-year follow-up, 12 out of 27 patients proceeded with primary or revision TKA. There were no cases of blood transfusion, nerve palsy, or compartment syndrome, and all patients achieved bony union.

Conclusions

Staged, extra-articular deformity correction is a safe and effective approach to improve limb alignment in the setting of knee osteoarthritis and TKA.

Management of medial femorotibial osteoarthritis: Epidemiology, and survival of unicompartmental knee arthroplasty versus valgus high tibial osteotomy in France. Study of 108,007 cases from the French National Hospitals Database

INTRODUCTION

Unicompartmental knee arthroplasty (UKA) and valgus high tibial osteotomy (HTO) are two options for isolated medial femorotibial osteoarthritis in genu varum. In the absence of registries for osteotomies and for arthroplasty in the knee, epidemiological data are hard to obtain in France. We therefore performed a retrospective study, with the aims of: 1) estimating UKA and HTO survival without revision by total knee arthroplasty (TKA), and 2) assessing risk factors for revision according to treatment group.

HYPOTHESIS

Medium-term survival is better with HTO than UKA in under-70-year-olds.

MATERIALS AND METHOD

All elderly patients undergoing HTO or UKA in the French National Hospitals Database for the period 2011-2020 were included: i.e., 108,007 patients; 43,537 HTO (29,330 male, 14,207 female; mean age 49.7 years, 95% CI 49.6-49.8) and 64,470 UKA (31,181 male, 33,289 female; mean age 60.5 years, 95% CI 60.5-60.6).

RESULTS

Survival free of revision by TKA was 75.8% (95% CI=75.2-76.4) for UKA and 80.6% (95% CI=80.0-81.3) for HTO (p<0.00001). In UKA, revision risk factors comprised: low annual center volume (<17 UKAs per year) (HR=1.50; 95% CI=1.41-1.59), obesity (HR=1.25; 95% CI=1.18-1.32), and age <60years, with maximum risk for 50-59years (HR=2.41; 95% CI=1.83-3.16 in 50-59 year-olds). In HTO, revision risk factors comprised: obesity (HR=1.42; 95% CI=1.31-1.53), rheumatoid arthritis (HR=2.75; 95% CI=1.37-5.51), joint chondrocalcinosis (HR=2.01; 95% CI=1.18-3.39), and age >60years (HR=8.81; 95% CI=7.23-19.73 in 60-69-year-olds). Male gender was a protective factor against revision in both groups: UKA, HR=0.75 (95% CI=0.72-0.79); HTO, HR=0.73 (95% CI=0.69-0.77). The number of UKAs increased over the years, matching the increase in arthroplasty in France, with a decrease in HTOs until 2019.

CONCLUSION

HTO showed better medium-term survival than UKA in under-70-year-olds in France. Even so, indications decreased in favor of UKA, although the respective risk factors differ. These findings suggest that conservative surgery still has a role, depending on osteoarthritis stage.

LEVEL OF EVIDENCE

III; retrospective comparative study.

Muti-factor analysis of sport activity level after high tibial osteotomy

BACKGROUND

Although many studies have shown that high tibial osteotomy is appropriate for active patients, there are limited multifactorial studies on patients' sport activity level after HTO in general population.

METHODS

158 patients who underwent HTO for knee osteoarthritis between January 2016 and December 2019 are included, with a 36-month follow-up. Information was collected from X-rays and questionnaire. The independent variables were age, sex, breadwinner (provide more than 50% income), sport activity level when the knee was pain-free before and after surgery, concomitant meniscal treatment history, Lysholm knee score, desire level for returning to sports. The 158 cases are divided into three groups according to their sports participation before and after operation, Chi-square tests and ANOVA analysis were adopted to identify the effect of these variables on sport activity level after HTO, and factors with statistical differences and clinical relevancies, or provided by previous research were assessed with the ordinal logistic regression analysis.

RESULTS

According to sport activity level analysis, 28(17.7%) patients were categorized into the sport level-reduced group, 97(61.4%) patients into the sport level-unchanged group, and 33(20.9%) patients into the sport level-improved group. Upon ordinal logistic regression analysis, postoperative MA%, age, BMI, and preoperative Lysholm knee score were statistically significant.

CONCLUSIONS

Higher postoperative MA%, younger age, lower BMI, and lower Lysholm score are associate with improvement on activity level after HTO. This finding provides valuable references in operation option and rehabilitation planning.

Total knee arthroplasty post-high tibial osteotomy, results of an early experience from a North African arthroplasty unit, and a comprehensive review of the literature

PURPOSE

To report an early experience after converting HTO to TKA by reporting the incidence of functional, radiological, and complications in a single surgeon case series from a North African specialized arthroplasty unit.

METHODS

Between 2010 and 2020, 33 knees in 31 patients (two bilateral) were operated upon, 24 females and seven males, had a mean age of 65 ± 4.5 years; 17 (51.5%) knees had medial wedge opening (WMO), while 16 (48.5%) had lateral wedge closure (LWC) osteotomies. The mean time from HTO to TKA was 8.1 ± 3.3 years. A posterior stabilized (PS) implant was used in 31 (93.9%), while in 2 (6.1%), a varus-valgus constrained (VVC) implant was used. A tibial stem was needed in 13 (39.4%) knees. The functional assessment was performed according to the Knee Society Scoring System (KSS). The radiographic assessment included the anatomical femorotibial angle (aFTA) for alignment, the medial proximal tibial angle (MPTA), and the tibial slope (TS).

RESULTS

After a mean follow-up of 4.3 ± 1.1 years, the KSS knee and function sub-scores improved from a preoperative mean of 41 ± 8.9 (26 to 57) and 37.7 ± 9.2 (25 to 55) points to 91.3 ± 3.8 (81 to 94) and 85.5 ± 5 (80 to 95) points at the last follow-up, respectively (P < 0.05). The preoperative knee flexion improved from a mean of 84.5° ± 15.9 (55 to 110) to 110.6° ± 9.3 (95 to 125) (P < 0.05). The aFTA improved from a preoperative mean of 182.2° ± 10.3 (164 to 205) to a postoperative mean of 186° ± 2.6 (179 to 190) (P < 0.05). The MPTA changed from a preoperative mean of 88.4° ± 6.7 (77 to 102) to a postoperative (tibial component alignment) mean of 90° ± 1.7 (85 to 94) (P < 0.05). The mean preoperative TS changed from 80.9° ± 7.3 (68 to 96) to a mean postoperative of 86.9° ± 1.3 (83 to 89) (P < 0.05). Non-progressive radiolucent lines were detected at the tibial component in four (12%) knees. Complications were reported in seven (21.2%) knees; no revision was needed in any knee.

CONCLUSIONS

The authors' early experience showed improved functional and radiological outcomes; however, the complication incidence was relatively high, but no knees required revision. A longer follow-up is mandatory to prove the consistency of the results.

Unicompartmental Knee Arthroplasty Provides Superior Clinical and Radiological Outcomes Compared to High Tibial Osteotomy at a Follow-Up of 5-8 Years

BACKGROUND

Knee Osteoarthritis (OA) is a debilitating disease. Initially, the medial compartments are affected in most cases. For this pathology, joint preservation is preferable. Two surgical procedures aim to meet this goal: high-tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA). The aim was to compare clinical and radiological outcomes of HTO versus UKA in patients with unicompartmental, medial OA.

METHOD

Retrospective case series. A total of 86 (61 UKA, 25 HTO) patients that received either treatment at a single, specialized center were assessed pre-operatively and at a single follow-up examination at 77.13 months (±8.170). The Knee Society Score (KSS), range of motion (ROM), SF36 questionnaire and the Tegner score were used. The Kellgren-Lawrence score was assessed pre- and post-surgically. Survivorship with the endpoint "revision" was assessed.

RESULTS

The UKA group showed significantly better improvements in KSS scores for pain (p < 0.006) and function (p < 0.001). OA progression (p < 0.02) and survivorship (p < 0.018) differed, significantly favoring UKA. ROM, SF36 and Tegner score did not differ significantly.

CONCLUSIONS

The presented mid-to long-term data suggest that UKA provides superior results in selected outcomes. Nevertheless, significant differences in the demographics of treatments indicate the challenge of comparing these two treatments.

Medial unilateral knee arthroplasty after high tibial osteotomy: A retrospective study of 41 cases

INTRODUCTION

When medial knee osteoarthritis continues to get worse after a high tibial osteotomy (HTO) procedure, a subsequent total knee arthroplasty (TKA) is typically warranted. Medial unilateral knee arthroplasty (UKA) is not recommended. The aim of this study was to evaluate the outcomes of patients who underwent medial UKA after HTO.

HYPOTHESIS

Good results can be obtained with this procedure, as long as the postoperative valgus is not excessive.

MATERIALS AND METHODS

This was a retrospective, single-center study of patients operated between January 2005 and June 2019. The primary endpoint was the Oxford Knee Scale (OKS). The Knee injury and Osteoarthritis Outcome Score (KOOS) and the Western Ontario and McMaster Universities osteoarthritis index (WOMAC), range of motion and complications were the secondary endpoints. The average follow-up was 79 months.

RESULTS

Forty-one knees in 38 patients were analyzed. Four revisions with implant exchange (10%) were needed. Thirty-seven knees had a mean OKS of 20/60±8 (12-39). The mean flexion and extension amplitude were 123°±8° (110-140) and -1.5°±4 (-15-0), respectively. Eight patients had flexion and/or extension contractures.

DISCUSSION

Good functional and clinical outcomes in the medium term were achieved for the patients in this study who underwent UKA after HTO. These findings reinforce the good results reported in recent studies of UKA after HTO.

LEVEL OF EVIDENCE

IV, Retrospective study.

Comparing Unicompartmental Knee Arthroplasty and High Tibial Osteotomy for Isolated Medial Compartment Knee Osteoarthritis

»

Both unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) allow for compartment-specific intervention on an arthritic knee joint that preserves bone stock and native soft tissue compared to a total knee arthroplasty (TKA). Both operations give a more natural feeling with native proprioception compared with a TKA.

»

HTO is better suited in patients who are younger (<55 years-of-age), have a body mass index (BMI) <30 kg/m2, high activity requirements, mechanical malalignment, asymmetric varus, isolated anterior cruciate ligament insufficiency, need for multiplanar correction, and a preference for joint preserving interventions. Recent data suggest that age (>55 years-of-age) should not solely contraindicate a HTO.

»

UKA may be chosen in patients who are older (>55 years-of-age), low activity requirements, have a BMI <40 kg/m2, severe osteoarthritis with significant joint space narrowing, acceptable coronal alignment, symmetric varus, and patient preference for arthroplasty.

Higher survival rate in total knee arthroplasty after high tibial osteotomy than that after unicompartmental knee arthroplasty

PURPOSE

The objective of this study was to evaluate the survival rates and complications in TKA after UKA and HTO as compared with primary TKA using national health data. It was hypothesized that survival and complication rates would be worse in patients with a history of UKA or HTO compared to primary TKA.

METHODS

Based on a list of patients who underwent TKA from Korean National Health Insurance database, 315,071 underwent primary TKA (group A); 2177 TKA after HTO (group B); and 1284 TKA after UKA (group C). Revision rates were compared between the groups using log-rank tests and adjusted hazard ratios (HR) of groups B and C were compared with those of the reference group (group A). A total of 1000 TKA matched patients were assigned to groups B and C according to propensity score for comparing revision rates after TKA and perioperative complication rates between TKA after HTO and UKA.

RESULTS

The overall revision rate was 2.1% in group A, 2.0% in group B, and 4.2% in group C. The revision rate until 10 years after TKA was significantly higher in group B (p = 0.03) or C (p < 0.0001) than in group A. The hazard ratios for revision was significantly higher in group A than in groups B and C at 10 years after index TKA (1.4 in group B and 3.7 in group C). The result of the comparison using PSM between TKA after HTO and UKA showed that TKA after HTO had lower risk of revision than TKA after UKA (HR: 0.41 at 10 years). However, no statistically significant differences in the perioperative complication rate between the two groups were found. (NS, not significant) CONCLUSIONS: TKA after UKA or HTO showed a significantly higher risk of revision than primary TKA. While TKA after HTO showed lower risk of revision than TKA after UKA, no significant differences in complications between TKA after UKA and HTO were found. Thus, surgeons must be aware of the low survival rate in TKA after UKA or HTO, especially in TKA after UKA.

LEVEL OF EVIDENCE

III (Retrospective cohort study).

Complications, Implant Survivorships, and Functional Outcomes of Conversion Total Knee Arthroplasty With Prior Hardware

BACKGROUND

End-stage knee osteoarthritis with retained periarticular hardware is a frequent scenario. Conversion total knee arthroplasty (TKA) leads to excellent outcomes, but poses unique challenges. The evidence supporting retention versus removal of hardware during TKA is controversial.

METHODS

Patients who underwent TKA with prior hardware between January 2009 and December 2019 were identified. A total of 148 patients underwent TKA with prior hardware. The mean follow-up was 60 months (range, 24-223). Univariate and multivariable analyses were used to study correlations among factors and surgical-related complications, prosthesis failures, and functional outcomes.

RESULTS

The complication rate was 28 of 148 (18.9%). The use of a quadriceps snips in addition to a medial parapatellar arthrotomy was associated with a higher complication (odds ratio: 20.7, P < .05), implant failures (odds ratio: 13.9, P < .05), and lower the Veterans Rand 12 Mental Score (VR-12 MS) (-14.8, P < .05). Hardware removal versus retention and use of single versus multiple incisions were not associated with complications or prosthesis failures. Removal of all hardware was associated with significantly higher (+7.3, P < .05) VR-12 MS compared to retention of all hardware.

CONCLUSIONS

TKA with prior hardware was associated with more complications, implant failures, and lower VR-12 MS when a more constrained construct or quadriceps snip was performed. This probably reflects the level of difficulty of the procedure rather than the surgical approach used. Hardware removal or retention was not associated with complications or implant failures; however, removal rather than retention of all prior hardware is associated with increased general health outcomes.

LEVEL OF EVIDENCE

IV, cohort without control.

Higher knee survivorship in young patients with monocompartmental osteoarthritis and constitutional deformity treated by high tibial osteotomy then total knee arthroplasty compared to an early total knee arthroplasty : a comparative study at a minimum follow-up of ten years

AIMS

The use of high tibial osteotomy (HTO) to delay total knee arthroplasty (TKA) in young patients with osteoarthritis (OA) and constitutional deformity remains debated. The aim of this study was to compare the long-term outcomes of TKA after HTO compared to TKA without HTO, using the time from the index OA surgery as reference (HTO for the study group, TKA for the control group).

METHODS

This was a case-control study of consecutive patients receiving a posterior-stabilized TKA for OA between 1996 and 2010 with previous HTO. A total of 73 TKAs after HTO with minimum ten years' follow-up were included. Cases were matched with a TKA without previous HTO for age at the time of the HTO. All revisions were recorded. Kaplan-Meier survivorship analysis was performed using revision of metal component as the endpoint. The Knee Society Score, range of motion, and patient satisfaction were assessed.

RESULTS

Mean follow-up was 13 years (SD 3) after TKA in both groups. The 20-year Kaplan-Meier survival estimate was 98.6% in TKA post-HTO group (HTO as timing reference) and 81.4% in control group (TKA as timing reference) (p = 0.030). There was no significant difference in clinical outcomes, radiological outcomes, and complications at the last follow-up.

CONCLUSION

At the same delay from index surgery (HTO or TKA), a strategy of HTO followed by TKA had superior knee survivorship compared to early TKA at long term in young patients.Level of evidence: IIICite this article: Bone Jt Open 2023;4(2):62-71.

Higher activity level after opening wedge high tibial osteotomy compared to medial unicompartimental knee arthroplasty in a selected cohort of advanced age: A propensity score-matched analysis

BACKGROUND

High tibial osteotomy (HTO) and medial unicompartmental knee arthroplasty (mUKA) are accepted treatment for medial knee osteoarthritis (OA). Patients often present meeting indications for both procedures. The purpose of this study was to compare results after MOWHTO and UKA in a matched population of patients older than 50 years.

METHOD

A retrospective analysis searching for patients older than 50 years meeting indication both for UKA and MOWHTO was performed. A propensity score matching (PSM) based on demographics and clinical data was performed. Tegner activity scale (TAS), Lysholm knee score (LKS) and numeric rating scale for pain (NRS) were recorded prospectively prior to surgery, at 6 months and after a minimum of 4 years.

RESULTS

64 UKA and 71 MOWHTO were found. Mean follow up was similar (54,05 ± 4,80 and 52,62 ± 3,91). A significant improvement was found in both groups for all outcomes at 6 months and at final follow up. PSM yielded 29 pairs. Patients treated with MOWHTO showed superior TAS scores at 6 months (3,41 ± 0,50 vs 3,10 ± 0,56; p < 0,05) and at final follow up (3,83 ± 0,80 vs 3,27 ± 0,59; p < 0,005). NRS and LKS were comparable between groups.

CONCLUSIONS

MOWHTO performed using an open wedge technique, with locking plate and a fast rehabilitation protocol guaranteed higher level of activity than UKA in patients older than 50 years. Difference is significant already at 6 months and last longer than 4 years.

LEVEL OF EVIDENCE

III.

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) ≤ 3^o valgus, neutral alignment (NA) 3-9^o valgus alignment, valgus alignment (VlA) ≥ 9^o 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.

Administrative Data Use in National Registry Efforts: Blessing or Curse?

"Big data" refers to a growing field of large database research. Administrative data, a subset of big data, includes information from insurance claims, electronic medical records, and registries that can be useful for investigating novel research questions. While its use provides salient advantages, potential researchers relying on big data would benefit from knowing about how these databases are coded, common errors they may encounter, and how to best use large data to address various research questions. In the first section of this paper, Dr. Nicholas A. Bedard addresses the four major pitfalls to avoid with diagnosis and procedure codes in administrative data. In the next section, Dr. Jeffrey N. Katz et al. focus on the strengths and limitations of administrative data, suggesting methods to mitigate these limitations. Lastly, Dr. Elena Losina et al. review the uses and misuses of large databases for cost-effectiveness research, detailing methods for careful economic evaluations.

Fixed-bearing unicompartmental knee arthroplasty provides a lower failure rate than mobile-bearing unicompartimental knee arthroplasty when used after a failed high tibial osteotomy: a systematic review and meta-analysis

Despite the fact that the choice of bearing design has been thought to influence the functional outcomes and longevity of unicompartimental knee arthroplasty (UKA), there is a lack of clinical evidence supporting the decision-making process in patients who have undergone high tibial osteotomy (HTO). A systematic review of studies was carried out that reported the outcomes of fixed-bearing (FB) or mobile-bearing (MB) medial UKA in patients with a previous HTO. A random effect meta-analysis using a generalized linear mixed-effects model to calculate revision rates was done. Seven retrospective cohort studies were included for this study. Regarding the fixation method, 40 were the FB-UKA and 47 were MB-UKA. For both groups, the mean post-operative follow-up was 5.8 years. The survival rates were 92% for the FB-UKA with a mean follow-up of 10 years. For the MB-UKA, it ranged from 35.7 to 93%, with a mean follow-up of 4.2 years. For the FB, the time to revision was reported as 9.3 years, while 1.2, 2.5 and 2.91 years was reported for the MB. The results of the meta-analysis showed that the revision rate for the patients receiving a FB-UKA after failed HTO was 8%, compared to 17% in those who received an MB-UKA. The results of the review suggest that the use of the FB-UKA is associated with lower revision rates and a longer survival time than the MB-UKA and have similar functional ability scores.Level of evidence: III (systematic review of level-III studies).

Medial unicompartmental knee replacement is a viable treatment option after failed high tibial osteotomy: a systematic review

Purpose

Methods

Results

Conclusions

Considerations of the Posterior Tibial Slope in Anterior Cruciate Ligament Reconstruction: a Scoping Review

PURPOSE OF REVIEW

The significance of posterior tibial slope (PTS) in the setting of anterior cruciate ligament (ACL) injury and reconstruction has been increasingly recognized in recent years. The purpose of this article is to review the biomechanical and clinical studies of PTS in conjunction with ACL injuries, providing an evidence-based approach for the evaluation and management of this patient population.

RECENT FINDINGS

Several biomechanical and clinical studies suggest that PTS > 12° may be considered with increased strain on the native ACL fibers (or reconstructed graft) and greater anterior tibial translation, predisposing patients to a recurrent ACL injury. The increased rates of ACL injury and graft failure seen in those with increased PTS have garnered attention to diagnose and surgically address increased PTS in the revision ACL setting; however, the role of a slope-reducing high tibial osteotomy (HTO) in primary ACL reconstruction (ACL-R) has yet to be defined. Various HTO techniques to decrease PTS during revision ACL-R have demonstrated promising outcomes, though conclusions are limited by the multifactorial nature of revision surgery and concomitant procedures performed. Recent evidence suggests that increased PTS is a risk factor for failure following ACL-R, which may be mitigated by a slope-reducing HTO. Further investigation is needed to elucidate abnormal PTS values and to determine appropriate indications for a slope-reducing HTO in primary ACL-R.

A Mid-Level Constrained Insert Reduces Coupled Axial Rotation but Not Coronal Mid-Flexion Laxity Induced by Joint Line Elevation in Posterior-Stabilized Total Knee Arthroplasty: A Computational Study

BACKGROUND

Surgeons may resect additional distal femur during primary posterior-stabilized (PS) total knee arthroplasty (TKA) to correct a flexion contracture. However, the resultant joint line elevation (JLE) increases mid-flexion laxity. We determined whether a mid-level constraint (MLC) insert reduced mid-flexion laxity after JLE.

METHODS

Six computational knee models were developed using computed tomography scans and average soft tissue properties yielding balanced extension gaps but with a 10° flexion contracture. Distal femoral resections of +2 and +4 mm were simulated with PS and MLC inserts. Varus-valgus ±10 Nm moments were applied at 30°, 45°, and 60° of flexion. Coronal laxity (the sum of varus-valgus angulation) and coupled axial rotation (the sum of internal/external rotation) were measured and compared between insert models.

RESULTS

At 30° of flexion, coronal laxities with the PS insert at the +2 and +4 mm resections averaged 7.9° ± 0.6° and 11.3° ± 0.6°, respectively, and decreased by 0.8° (P = .06) and 1.0° (P = .07), respectively, with the MLC insert. PS rotational laxities at the +2 and +4 mm resections averaged 11.1° ± 3.9° and 12.5° ± 4.6°, respectively, and decreased by 5.6° (P = .01) and 7.1° (P = .02), respectively, with the MLC insert. Similar patterns were observed at 45° and 60° of flexion.

CONCLUSION

With additional distal femoral resections to alleviate a flexion contracture, utilizing an MLC insert substantially reduced coupled axial rotation but had a minimal impact on coronal laxity compared to a PS insert. Efforts should be taken to avoid JLE in primary total knee arthroplasty as even MLC inserts may not mitigate coronal laxity.

Total Knee Arthroplasty Function at 25 Years Following Proximal Tibial Osteotomy: Paired Outcomes of Bilateral TKAs Following Unilateral Osteotomy

BACKGROUND

Proximal tibial osteotomy (PTO) is a well-established treatment for coronal deformity and focal cartilage defects. However, the utility of joint-preserving interventions must be weighed against potential effects on subsequent total knee arthroplasty (TKA). The purpose of this study was to determine the effect of PTO on subsequent TKA by comparing outcomes in patients with bilateral TKAs following unilateral PTO.

METHODS

Patients who underwent bilateral TKAs from 2000 to 2015 at a single institution and had previously undergone a unilateral valgus-producing PTO were reviewed. We evaluated 140 TKAs performed in 70 patients (24 female, 46 male) with a mean age at PTO of 50 ± 8 years. The patients underwent conversion to TKA at a mean of 14 ± 7 years following ipsilateral PTO and were followed for a mean of 25 ± 7 years (range, 6 to 40 years) following PTO. The Knee Society Score (KSS), Forgotten Joint Score-12 (FJS-12), subjective knee preference, and revision were compared between the PTO-TKA and contralateral TKA-only sides.

RESULTS

The PTO side demonstrated similar KSS Knee subscores (41 ± 16) compared with the contralateral side (39 ± 16, p = 0.67) immediately prior to arthroplasty. Patients had significant improvements in KSS (p < 0.001) after TKA, with clinically similar KSS values at 2 to 15 years of follow-up when knees were compared in a pairwise fashion (p = 0.10 to 0.83). Five PTO-TKA knees (7%) and 4 control TKA-only knees (6%) underwent revision at a mean of 5 years postoperatively (p = 0.76). The number of all-cause reoperations was approximately twice as high in PTO-TKA knees (13% compared with 6% in TKA-only knees, p = 0.24). At the time of final follow-up, PTO-TKA knees demonstrated similar FJS-12 scores (72 ± 26) compared with the contralateral knees (70 ± 28, p = 0.57). Nineteen percent of patients preferred the PTO-TKA knee, 19% preferred the contralateral TKA-only knee, and 62% stated that their knees were equivalent (p > 0.99). The final Tegner activity score was 2.5 ± 1.4.

CONCLUSIONS

Long-term clinical function of TKA following PTO was excellent, with patients demonstrating comparable subjective outcomes and equivalent knee preference compared with the contralateral TKA-only knees. Further, well-matched studies are needed to evaluate long-term revision and reoperation rates following PTO-TKA.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Long-term survival rate of closing wedge high tibial osteotomy with high valgus correction: a 15-year follow-up study

PURPOSE

The influence of closing wedge high tibial osteotomy (CW-HTO) with high valgus correction on its survival is unclear. This study aimed to conduct a 15-year follow-up cohort study to estimate the long-term survival rate of CW-HTO. Factors related to poor outcomes were investigated.

METHODS

A total of 159 knees in 123 patients were followed up, and 120 knees in 96 patients were enrolled for statistical analysis. Femorotibial angles were measured by standing anterior-posterior radiographs of the knee. Clinical objective evaluation was performed by the Japanese orthopaedic association (JOA) score of the knee, and scores lower than 70 points defined the poor result (PR) group. The survival rate of OW-HTO was estimated. Logistic regression analyses were performed to determine the risk factors for PR and conversion to total knee arthroplasty (TKA).

RESULTS

A total of 16 knees in 15 patients (13.3%) underwent TKA 14.0 ± 4.8 (4-20) years after CW-HTO. The 5-year survival rate was 99.2%, 10-year was 96.7%, 15-year was 92.5%, and 86.7% at final follow-up (17.9 years). Based on the JOA score, 44 patients (35.8%) belonged to the PR group, and their risk factors were obesity (p = 0.018), low femorotibial angle (p = 0.019), low JOA score (p = 0.040), low knee extension angle (p = 0.045), and low knee flexion angle (p = 0.046).

CONCLUSIONS

The 15-year survival rate of CW-HTO was 92.5%. While higher scores of objective outcomes were kept over long-term follow-up, the risk factors for a worsening score or TKA conversion were obesity and severity of preoperative knee symptoms.

Conversion Total Knee Arthroplasty

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Conversion total knee arthroplasty (TKA) represents a heterogeneous group of procedures and most commonly includes TKA performed after ligamentous reconstruction, periarticular open reduction and internal fixation (ORIF), high tibial osteotomy (HTO), and unicompartmental knee arthroplasty (UKA).

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Relative to patients undergoing primary TKA, patients undergoing conversion TKA often have longer operative times and higher surgical complexity, which may translate into higher postoperative complication rates.

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There is mixed evidence on implant survivorship and patient-reported outcome measures when comparing conversion TKA and primary TKA, with some studies noting no differences between the procedures and others finding decreased survivorship and outcome scores for conversion TKA.

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By gaining an improved understanding of the unique challenges facing patients undergoing conversion TKA, clinicians may better set patient expectations, make intraoperative adjustments, and guide postoperative care.

Osteomyelitis variolosa, an issue inherited from the past: case report and systematic review

Background

Osteomyelitis variolosa is a self-limiting disease triggered by variola virus that cannot be prevented or repaired. Smallpox has been eradicated for 40 years, and complications that remain after smallpox has been cured have become a remarkable diagnostic challenge for contemporary physicians. In this systematic review, we searched PubMed (MEDLINE), Web of Science, and Google Scholar for cases on complications, diagnosis, and treatment for osteomyelitis variolosa between January 1980 and February 2021.

Results

Ten papers and eleven finished cases, all patients from India, were included for comparison with the present case. In total, 100% of patients presented with bilateral elbow deformities, the ankle was the second most common site of lesion in 50%, and knee lesions accounted for 25% in this study. Flexion contracture, joint instability, secondary arthritis, and fracture are common complications of osteomyelitis variolosa, and most patients receive conservative treatment, while internal fixation has good results for combined fractures.

Conclusions

Although osteomyelitis variolosa is not a direct threat to the safety of patients, severe skeletal deformities can have a significant impact on quality of life. With advances in surgical techniques, clinicians are offering an increasing number of treatment options for patients with osteomyelitis variolosa. However, most importantly, smallpox has basically been removed from the historical arena, and for areas where smallpox was once endemic, physicians need to deepen the understanding of this disease again.

Medial Unicompartmental Knee Arthroplasty After Failed Open-Wedge High Tibial Osteotomy

BACKGROUND

Controversy exists whether or not a previous high tibial osteotomy (HTO) influences the outcome and survival of a unicompartmental knee arthroplasty (UKA). The aim of this retrospective study was to evaluate clinical, radiological, and functional outcomes of UKA after failed open-wedge HTO compared with UKA with no previous HTO.

METHODS

Between 2001 and 2017, 24 post-HTO UKAs (group A) with an average follow-up of 8.1 years (range: 5 to 13) were compared with a control group of 30 patients undergoing simple UKA (group B) with an average follow-up of 9.5 years (range: 2 to 16). All patients were evaluated preoperatively and postoperatively using Knee Society Score, University of California at Los Angeles Activity Score, Western Ontario and McMaster University Osteoarthritis Index, and through objective evaluation. Mechanical coronal alignment and Caton-Deschamps index were measured both preoperatively and postoperatively.

RESULTS

In both groups, Knee Society Score, University of California at Los Angeles Activity Score, and Western Ontario and McMaster University Osteoarthritis Index scores significantly improved at follow-up (P < .001). In addition, statistically significant greater improvements in clinical and functional scores were reported in group B compared with group A (P < .001). No statistically significant differences concerning postoperative mechanical axis were observed between groups (2.7° and 3.2°, respectively, P = .27) and with regard to Caton-Deschamps index (1.0° and 1.1°, respectively, P = .44).

CONCLUSION

This study demonstrated improvements in clinical and functional outcomes compared with preoperatory status in both groups irrespective of a previous HTO. A prior HTO was a determinant for having reduced postoperative clinical and functional outcomes after UKA.

High Tibial Osteotomy for Varus Deformity of the Knee

High tibial osteotomy is a powerful technique to treat symptomatic varus deformity of the knee and is successful when properly indicated and performed. Indications include varus deformity with medial compartment osteoarthritis, cartilage or meniscus pathology. Several techniques exist to correct symptomatic varus malalignment along with concomitant procedures to restore cartilage or meniscus injuries. Evidence supporting high tibial osteotomy for symptomatic medial compartment pathology exists, which provides a durable solution for joint preservation. This review will discuss the indications, techniques, and outcomes for high tibial osteotomies used in the treatment of symptomatic varus deformity of the knee.

High Rate of Re-Revision in Patients Less Than 55 Years of Age Undergoing Aseptic Revision Total Knee Arthroplasty

BACKGROUND

There are limited data on the outcomes of revision total knee arthroplasty in young patients. We sought to characterize the re-revision-free survival and risk factors for re-revision in patients less than 55 years who underwent aseptic revision TKA.

METHODS

We retrospectively reviewed 197 revision TKAs at a mean follow-up of 5 years. Mean age was 49 years; mean body mass index was 31 kg/m². Twenty-seven (14%) patients had at least 1 prior revision TKA. The most common indications for revision included instability (29%), arthrofibrosis (26%), and aseptic loosening (24%). Constraint included the following: 59 posterior-stabilized (30%), 123 varus-valgus constrained (62%), and 15 hinged (8%). Components revised included the following: 93 femur/tibia (47%), 68 polyethylene-only (35%), 19 femur-only (10%), and 17 other (9%). Survivorship free from re-revision was calculated via the Kaplan-Meier method and a multivariate Cox proportional regression was utilized to identify risk factors for re-revision.

RESULTS

Survivorship free from any re-revision at 5 years was 80%. In the multivariate analysis, patients with a prior revision (hazard ratio [HR] = 2.78, P = .02), an isolated polyethylene exchange (HR = 3.0, P = .004), and a hinged prosthesis (HR = 3.47, P = .05) were significant risk factors for lower revision-free survival. Forty-two patients (21%) underwent re-revision, most commonly for periprosthetic joint infection (7%), instability (6%), and aseptic loosening (5%). Re-revision occurred in 18/68 (26%) patients undergoing an isolated polyethylene exchange.

CONCLUSION

Patients less than 55 years undergoing revision TKA have a modest 5-year revision-free survival of 80%. Patients with prior revision TKAs (HR = 2.78), hinge type prostheses (HR = 3.47), and polyethylene-only revisions (HR = 3.0) had higher revision rates.

Additional distal femoral resection increases mid-flexion coronal laxity in posterior-stabilized total knee arthroplasty with flexion contracture : a computational study

AIMS

Surgeons commonly resect additional distal femur during primary total knee arthroplasty (TKA) to correct a flexion contracture, which leads to femoral joint line elevation. There is a paucity of data describing the effect of joint line elevation on mid-flexion stability and knee kinematics. Thus, the goal of this study was to quantify the effect of joint line elevation on mid-flexion laxity.

METHODS

Six computational knee models with cadaver-specific capsular and collateral ligament properties were implanted with a posterior-stabilized (PS) TKA. A 10° flexion contracture was created in each model to simulate a capsular contracture. Distal femoral resections of + 2 mm and + 4 mm were then simulated for each knee. The knee models were then extended under a standard moment. Subsequently, varus and valgus moments of 10 Nm were applied as the knee was flexed from 0° to 90° at baseline and repeated after each of the two distal resections. Coronal laxity (the sum of varus and valgus angulation with respective maximum moments) was measured throughout flexion.

RESULTS

With + 2 mm resection at 30° and 45° of flexion, mean coronal laxity increased by a mean of 3.1° (SD 0.18°) (p < 0.001) and 2.7° (SD 0.30°) (p < 0.001), respectively. With + 4 mm resection at 30° and 45° of flexion, mean coronal laxity increased by 6.5° (SD 0.56°) (p < 0.001) and 5.5° (SD 0.72°) (p < 0.001), respectively. Maximum increased coronal laxity for a + 4 mm resection occurred at a mean 15.7° (11° to 33°) of flexion with a mean increase of 7.8° (SD 0.2°) from baseline.

CONCLUSION

With joint line elevation in primary PS TKA, coronal laxity peaks early (about 16°) with a maximum laxity of 8°. Surgeons should restore the joint line if possible; however, if joint line elevation is necessary, we recommend assessment of coronal laxity at 15° to 30° of knee flexion to assess for mid-flexion instability. Further in vivo studies are warranted to understand if this mid-flexion coronal laxity has negative clinical implications. Cite this article: Bone Joint J 2021;103-B(6 Supple A):87-93.

Manipulation under anaesthesia after primary total knee arthroplasty : minimal differences in intravenous sedation alone versus neuraxial anaesthesia

AIMS

Manipulation under anaesthesia (MUA) remains an effective intervention to address restricted range of motion (ROM) after total knee arthroplasty (TKA) and occurs in 2% to 3% of primary TKAs at our institution. Since there are few data on the outcomes of MUA with different anaesthetic methods, we sought to compare the outcomes of patients undergoing MUA with intravenous (IV) sedation and neuraxial anaesthesia.

METHODS

We identified 548 MUAs after primary TKA (136 IV sedation, 412 neuraxial anaesthesia plus IV sedation) from March 2016 to July 2019. The mean age of this cohort was 62 years (35 to 88) with a mean body mass index of 31 kg/m² (18 to 49). The mean time from primary TKA to MUA was 10.2 weeks (6.2 to 24.3). Pre-MUA ROM was similar between groups; overall mean pre-MUA extension was 4.2° (p = 0.452) and mean pre-MUA flexion was 77° (p = 0.372). We compared orthopaedic complications, visual analogue scale (VAS) pain scores, length of stay (LOS), and immediate and three-month follow-up knee ROM between these groups.

RESULTS

Following MUA, patients with IV sedation had higher mean VAS pain scores of 5.2 (SD 1.8) compared to 4.1 (SD = 1.5) in the neuraxial group (p < 0.001). The mean LOS was shorter in patients that received IV sedation (9.5 hours (4 to 31)) compared to neuraxial anaesthesia (11.9 hours (4 to 51)) (p = 0.009), but an unexpected overnight stay was similar in each group (8.6%). Immediate-post MUA ROM was 1° to 121° in the IV sedation group and 0.9° to 123° in the neuraxial group (p = 0.313). Three-month follow-up ROM was 2° to 108° in the IV sedation group and 1.9° to 110° in the neuraxial anaesthesia group (p = 0.325) with a mean loss of 13° (ranging from 5° gain to 60° loss), in both groups by three months. No patients in either group sustained a complication.

CONCLUSION

IV sedation alone and neuraxial anaesthesia are both effective anaesthetic methods for MUA after primary TKA. Surgeons and anaesthetists should offer these anaesthetic techniques to match patient-specific needs as the orthopaedic outcomes are similar. Also, patients should be counselled that ROM following MUA may decrease over time. Cite this article: Bone Joint J 2021;103-B(6 Supple A):126-130.

[The influence of axial deformities and their correction on the development and progression of osteoarthritis]

Die Beachtung der Beinachse und die Möglichkeiten zur deren Korrektur stellen beim jungen Patienten mit Arthrose ein Grundpfeiler der Therapie dar. Die Kombination einer Gelenksverletzung und einer Achsdeviation führt unweigerlich, je nach Ausmaß und Komorbiditäten, schon nach wenigen Jahren zur fortschreitenden Gonarthrose. Neben der genauen Deformitätenanalyse zur Osteotomieplanung, gilt es, Normbereiche der entsprechenden Winkel zu kennen und eine Zielgröße zur Achskorrektur festzulegen. Aus dem Repertoire der verschiedenen kniegelenksnahen Osteotomien sind dann die Nebeneffekte in Bezug auf patellofemorales Maltracking, ligamentäres Balancing und die Beinlänge abzuschätzen. Gerade im Hinblick auf mögliche (und wahrscheinliche) Folgeoperationen beim jungen Patienten müssen neue knöcherne Deformitäten oder ligamentäre Insuffizienzen, welche potenziell bei Überkorrektur entstehen, unbedingt vermieden werden.

Patient-specific instrumentation (PSI) Referencing High Tibial Osteotomy Technological Transfer and Education: protocol for a double-blind, randomised controlled trial (PROTECTED HTO Trial)

INTRODUCTION

High tibial osteotomy (HTO) is a treatment of choice for active adult with knee osteoarthritis. With advancement in CT imaging with three-dimensional (3D) model reconstruction, virtual planning and 3D printing, patient-specific instrumentation (PSI) in form of cutting jigs is employed to improve surgical accuracy and outcome of HTO. The aim of this randomised controlled trial (RCT) is to explore the surgical outcomes of HTO for the treatment of medial compartment knee osteoarthritis with or without a 3D printed patient-specific jig.

METHODS AND ANALYSIS

A double-blind RCT will be conducted with patients and outcome assessors blinded to treatment allocation. This meant that neither the patients nor the outcome assessors would know the actual treatment allocated during the trial. Thirty-six patients with symptomatic medial compartment knee osteoarthritis fulfilling our inclusion criteria will be invited to participate the study. Participants will be randomly allocated to one of two groups (1:1 ratio): operation with 3D printed patient-specific jig or operation without jig. Measurements will be taken before surgery (baseline) and at postoperatively (6, 12 and 24 months). The primary outcome includes radiological accuracy of osteotomy. Secondary outcomes include a change in knee function from baseline to postoperatively as measured by three questionnaires: Knee Society Scores (Knee Scores and Functional Scores), Oxford Knee Scores and pain visual analogue scale (VAS) score.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Joint Chinese University of Hong Kong - New Territories East Cluster Clinical Research Ethics Committee (CREC no. 2019.050), in accordance with the Declaration of Helsinki. The results will be presented at international scientific meetings and through publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04000672; Pre-results.

Postoperative Psychosocial Factors in Health Functioning and Health-Related Quality of Life After Knee Arthroplasty: A 6-Month Follow up Prospective Observational Study

OBJECTIVE

Knee arthroplasty (KA) is an effective and cost-effective treatment for end-stage knee osteoarthritis. Despite high surgical success rates, as many as 25% of patients report compromised postoperative functioning, persistent pain, and reduced quality of life. The purpose of this study was to assess the predictive value of psychological factors in health functioning and quality of life, during a 6-month period after KA.

DESIGN

A prospective observational study.

SETTING

Surgery at two hospitals and follow-up was carried out through the domiciliary rehabilitation service.

SUBJECTS

In total, 89 patients (age 70.27 ± 7.99 years) met the inclusion criteria.

METHOD

A test battery composed of Health functioning associated with osteoarthritis (WOMAC), Health-related quality of life (EQ-5D-5L), Anxiety and Depression (HADS), Pain attitudes (SOPA-B), Pain catastrophizing (PCS), and Fear of Movement (TSK-11) was assessed at 1 week, and 1, 3, and 6 months after surgery. A mixed effects linear model was used to estimate the effect of time and covariates. An exploratory factor analysis was used to identify the number of dimensions underlying the group of psychological measurements.

RESULTS

In WOMAC model, anxiety level (F = 120.8), PCS (F = 103.9), depression level (F = 93.6) and pain score (F = 72.8) were the most influential variables. Regarding EQ-5D-5L model, anxiety level (F = 98.5), PCS (F = 79.8), depression level (F = 78.3) and pain score (F = 45) were the most influential variables. Pain score and the psychosocial variables of PCS, TSK, HADS-A, HADS-D, SOPA-B Emotion, SOPA-B Harm and SOPA-B Disability loaded in one single dimension.

CONCLUSIONS

Postoperative acute pain and psychosocial factors of pain catastrophizing, anxiety, depression, and pain attitudes might influence health functioning and quality of life during KA rehabilitation. Such factors could be gathered into one single dimension defined as pain-related psychologic distress.

High Midterm Survival Rate of Uncemented Total Knee Arthroplasty After High Tibial Osteotomy: A Case-Control Study

BACKGROUND

Total knee arthroplasty (TKA) following high tibial osteotomy (HTO) is technically more demanding than TKA in a native knee. Studies have reported increased intraoperative and postoperative complication of TKA with previous HTO. The aim of this study is to compare the survival and complication rates and functional outcomes of uncemented TKA with previous HTO to primary TKA at our institution over a decade.

METHODS

This case-control study included 41 uncemented TKA after HTO between 2002 and 2012. For each case, 2 control patients were matched based on age and gender without previous HTO. The 2 groups were comparable for body mass index, as well as preoperative functional scores.

RESULTS

The mean follow-up was 7.8 ± 2.4 (range, 5-13.6) years. At last follow-up, there was no significant difference in functional outcomes or radiological imaging, particularly the rate of radiological loosening. There was no significant difference in complications (9; 22%) in the group of TKA after HTO vs the control group (14; 17%). One revision was performed in the group of TKA after HTO for septic loosening, and no revisions in the control group. The survival rate at a mean follow-up of 8 years was 97.6% in the group TKA after HTO vs 100% in the control group.

CONCLUSION

Uncemented TKAs following HTO have no significant difference in functional and radiological outcomes and survivorship compared to uncemented primary TKA at midterm follow-up.