Knee Society Function Score Research Articles

Return to sports activity after opening wedge high tibial osteotomy in patients aged 70\xa0years and older

BackgroundThe purpose of this study was to evaluate return to sports (RTS) after opening wedge high tibial osteotomy (OWHTO) in elderly patients and associated factors affecting RTS.MethodsSeventy-four patients (mean age 68 years) who underwent OWHTO were enrolled. Clinical outcomes were evaluated using the Knee Society Score (KSS). Patients were asked regarding types of sports activities and their levels of participation within preoperative 1 year and postoperative 1 year. Levels of participation in sports and recreational activities were examined using the Tegner activity scale. The outcomes were compared between two age groups (≥ 70 years vs. < 70 years).ResultsOf the 74 patients overall, 59 participated in at least one sport preoperatively, and 55 returned to sports postoperatively (RTS 93%). The KSS knee score and function score were significantly improved after surgery in both age groups (P < 0.05), but no significant differences were found between the age groups. The Tegner activity scales for ≥ 70 years and < 70 years were 2.9 ± 1.1 and 4.0 ± 1.9 preoperatively (P < 0.01) and 2.7 ± 1.2 and 3.3 ± 1.4 postoperatively (P = 0.16), respectively. RTS was reported by 24 of 25 (96.0%) in the age < 70 years group and 31 of 34 (91.2%) in the age ≥ 70 years group. Majority of age ≥ 70 years participated in low-impact sports preoperatively and returned to the same impact level postoperatively.ConclusionsThe rate of RTS after OWHTO was high in patients aged 70 years and older with low-impact level. OWHTO is a preferred surgical option for elderly patients who desire RTS.

No difference in long-term functional outcomes or survivorship after total knee arthroplasty with or without computer navigation: a 17-year survivorship analysis

BackgroundThe literature comparing the long-term outcomes and survivorship of computer navigation-assisted and conventional total knee replacement (TKR) is sparse. Moreover, of the available comparative studies with follow-up duration of more than 10 years, the results seem to be conflicting. The purpose of this long-term study was to compare the clinical and radiological outcomes, and implant survivorship, of TKR performed with and without computer navigation.MethodsWe retrospectively compared the results of 49 computer-navigated TKRs and 139 conventional TKRs. The mean age of the patients was 67.9 (range 52–81) years for the navigation group and 67.1 (range 50–80) years for the conventional TKR group. The mean duration of follow-up for the conventional and navigation TKR groups was 12.9 and 13.2 years, respectively. Clinical and radiographic follow-up examinations of the patients were performed at 2 weeks, 1 month, 3 months and 6 months post-operatively, and at 1-year intervals thereafter.ResultsThere were no significant differences in the post-operative Knee Society knee and function score between the two groups. The mean overall deviation from neutral alignment and the radiological outliers were significantly higher in the conventional TKR group. The overall survival rates at 17 years were 92.9% for the navigation group and 95.6% for the conventional TKR group (p = 0.62).ConclusionsNavigated TKR resulted in fewer radiological outliers; however, this did not translate to better long-term functional outcomes or implant survival.

Clinical efficacy of bone transport technology in Chinese older patients with infectious bone nonunion after open tibial fracture

ObjectiveThis study was designed for the first time to analyze clinical efficacy of bone transport technology in Chinese older patients with infectious bone nonunion after open tibial fracture.MethodsThis study retrospectively analyzed 220 older patients with infectious bone nonunion after open tibial fracture. There were 110 patients receiving bone transport technology (Group A) and 110 patients receiving membrane induction technique with antibiotic bone cement (Group B).ResultsThere were 164 male patients and 56 female patients, with an age range of 65 to 71 years and an average age of 67 ± 1.3 years. Traffic accident, high-fall injury and crush injury account for 45.5, 27.7 and 26.8%, respectively. Age, gender, histories, causes and fracture location had no significant difference between the two groups (P > 0.05 for all). Operation time in the Group A was significantly shorter than that in the Group B (P < 0.05). Linear and positional alignment (70.9 vs. 57.3), American Knee Society knee function score (167.7 ± 14.9 vs. 123.8 ± 15.7), Baird-Jackson ankle function score (89.9 ± 3.5 vs. 78.4 ± 4.9), bone healing index (43.0 ± 2.0 vs. 44.3 ± 3.0) and clinical recovery (8.2 vs. 4.5) of patients in the Group A were significantly better than those in the Group B (P < 0.05 for all). Wound infection in the Group A (7.3%) was significantly less than that in the Group B (16.4%; P < 0.05). There were neither a neurovascular complication nor a recurrence of infection in the two groups.ConclusionBone transport technology achieved better knee and ankle joint function recovery and superior bone healing and clinical efficacy than membrane induction technique with antibiotic bone cement, suggesting that bone transport technique is worthy of extensive promotion to improve clinical condition of older patients with infectious bone nonunion after open tibial fracture.

The long-term results of total knee arthroplasty in octogenarian.

Aims: With increasing life expectancy and ageing population, more octogenarians would benefit from total knee arthroplasty (TKA). The aim of this study is to evaluate the survivorship of TKA in octogenarian and their long-term outcomes. Methods: This was a retrospective review of 67 patients aged above 80years who had primary TKA performed between 2005 and 2013 at a single centre. A sex-matched younger cohort of 67 primary TKAs during the same time-period was recruited for control. Five and 10-year survival was calculated. Pre- and peri-operative factors were collected and compared. Post-operative range of motion, Knee Society Score (KSS) and Function Score (KFS) were collected and compared. Rate of revision, infection, aseptic loosening and mortality was collected. Results: The mean follow-up period was 10.39 ± 2.29years. The 5- and 10-year survival of octogenarian group was 85.1% and 54.6%, respectively. Pre- and peri-operative factors between the octogenarian and control groups were comparable (p > 0.05). Both groups showed improvement in range of motion, KSS and KFS post-operatively. Rate of revision, aseptic loosening and deep infection was 0% in octogenarian and 1.5% in control group. Conclusion: TKA can be performed in patients with age above 80 years old with comparable post-op knee range, complication rate and long-term functional score. Advanced age should not be a limiting factor for TKA.

Increased posterior translation but similar clinical outcomes using ultracongruent instead of posterior stabilized total knee arthroplasties in a prospective randomized trial.

The aim of this study was to compare the posterior tibial translation after ultracongruent (UC) and posterior-stabilized (PS) total knee arthroplasty (TKA) with two different UC with different heights in the anterior lip, and two different PS designs. This study also aimed to compare the range of motion (ROM) and outcomes scores after the use of these TKA models. It was hypothesised less posterior tibial translation after PS than after UC TKA, and less posterior tibial translation with a higher anterior lip in the UC insert than with a lower one. It was designed as a prospective randomized study of a group of 120 patients operated with a cemented TKA. To clarify the main purpose of the study, four groups were analysed using different polyethylene designs: Triathlon PS insert in group one, Triathlon UC insert in group two, U2 PS insert in group three and U2 UC insert in group four. One year after surgery, a forced posterior drawer with a Telos Stress applying 15kg of force posteriorly on the proximal tibia at 90° of knee flexion was analysed in the lateral radiograph. Limb alignment, tibial posterior slope and posterior condylar offset were also studied. 30 patients were included in each group. The average age was 73years. There were 72.2% female and 27.8% male patients. There were no significant differences in any demographic or radiographic studied variables, preoperative range of motion (ROM) or preoperative Knee Society Scores (KSS) among the different groups. One year after surgery, the average postoperative ROM and the postoperative KSS Knee and KSS Function scores improved in respect of the preoperative values in all the groups. There were no significant differences in the postoperative outcome scores among the different groups (p = n.s.). Postoperative alignment of the limb, tibial posterior slope and posterior condylar offset were similar in the 4 study groups (p = n.s.). The postoperative posterior tibial translation was different between groups: the PS groups (groups 1 and 3) showed significant inferior values (p < 0.001) in respect of the UC groups (groups 2 and 4). There were no differences between both groups of PS models, but there was a significant increase in the posterior tibial translation of the Triathlon UC insert (11.2mm SD 3.2) in respect of the U2 UC insert (6.1mm SD 4.5) (p = 0.004). UC inserts restrict the posterior tibial translation after TKA less than PS inserts, but a design with a high anterior lip in the polyethylene UC insert can better control the posterior tibial translation than an insert with a small anterior lip. Level I. Randomised controlled trial.

The Impact of a Gap Balancing or Measured Resection Surgical Technique on Posterior Condylar Offset and Patient-Reported Outcome Measures.

BackgroundTo increase total knee arthroplasty procedure satisfaction, surgeons are exploring improvements in surgical technique. The impact of gap balancing or measured resection approach on posterior condylar offset (PCO) is not well understood.MethodsWe reviewed the clinical and radiographic results of 498 unilateral posterior stabilized total knee arthroplasties. Radiographs were assessed to measure the primary endpoints of anterior-posterior width, PCO, and anterior condylar offset. Clinical outcome measures were used to assess patient improvement measures. Multiple linear regression analyses were performed to determine the clinical factors related to our primary endpoints.ResultsNo significant difference was observed between groups in anterior-posterior width (P = .24) and PCO (P = .78). Significant positive correlations were observed between postoperative PCO and knee range of motion (r = 0.12, P = .04) and total Knee Society Scores (r = 0.14, P = .02).ConclusionNo impact of surgical technique on PCO was observed. Correlations were observed between postoperative PCO and the functional subscore and total Knee Society Score. All patients reported clinical improvements at 1 year postoperatively.

Influence of patellar denervation on anterior knee pain and knee function following total knee replacement: a systematic review and meta-analysis.

Previous studies have reached mixed results regarding the effects of patellar denervation with electrocautery (PD) on total knee replacement (TKR). This systematic review and meta-analysis aimed to summarize all available literatures to investigate the influence of PD on postoperative anterior knee pain (AKP) and knee function after TKR. Electronic databases, including PubMed, Cochrane Library and Embase, were searched from their inception to March 2021. Randomized controlled trials (RCT) and quasi-randomized controlled trials (quasi-RCT) comparing PD and non-patellar denervation (NPD) in TKR were selected, and the Cochrane risk of bias tool was used to assess the quality of included trials. AKP prevalence was defined as the primary outcome. A total of 12 RCTs and one quasi-RCT enrolled 1895 knees proved eligible. PD knees had significantly lower AKP prevalence than NPD knees (odds ratio [OR]=0.54; 95% confidence intervals [95% CI], 0.36-0.81; p=0.003). There was no difference between PD and NPD in terms of visual analogue scale for knee pain and range of motion, American knee society knee score, American knee society function score, patellar feller score, Oxford knee score for knee function. The results of subgroup analysis based on follow-up duration and patella resurfacing were in accordance with the results. PD knees were not associated with a higher risk of complication or revision. PD can significantly reduce the AKP prevalence following TKR without increasing the risk of complication and revision. Although the pain relief effect of PD may not be associated with improved knee function after TKR, this procedure is preferred in both patella resurfacing and patella non-resurfacing TKR.

Retrospective matched case-control study evaluating cementless total knee replacements in patients with BMI over 30 kg/m2 or in patients aged 65 yr and younger

Background: This study’s goal was to compare outcomes in cemented and cementless total knee arthroplasty (TKA) in patients with a body mass index of 30 kg/m2 or greater or patients aged 65 yr or younger. Methods: A retrospective matched case-control study was performed on 400 consecutive primary TKAs at the same community-based teaching institution by a single fellowship-trained arthroplasty surgeon. One hundred and eighty-six patients met the inclusion criteria for the obese cohort (93 cementless, 93 cemented). One hundred and seventy-one patients met the inclusion criteria of 65 yr of age or younger cohort (85 cementless, 86 cemented). Charts were reviewed for demographics, TKA revisions, Knee Society Score-Knee (KSS-Knee), Knee Society Score-Function (KSS-Function), Knee Injury and Osteoarthritis Outcomes Scores for Joint Replacement outcome scores, and perioperative complications. Results: The average follow-up was 4 years (range 2.5 to 7 yr). Patients demonstrated improved change for minimal clinically important differences values in both the cementless and cemented TKA groups for KSS-Knee and KSS-Function in each cohort. Substantial clinical benefit had improved change for cementless TKAs in both KSS-Knee and KSS-Function scores; however, only the cementless TKA group achieved an improved change in substantial clinical benefit with KSS-Function. Knee Injury and Osteoarthritis Outcomes Scores for Joint Replacement scores were equivalent between both the cementless and cemented cohorts. Conclusions: This study was clinically significant as outcome data remained positive for longer term follow-up in patients with a body mass index of 30 kg/m2 or greater or those aged 65 yr or younger with cementless total knees. Level of Evidence: Level III.

Total Knee Arthroplasty in Octogenarians: Should We Still Be so Restrictive?

Demand for total knee arthroplasty (TKA) in octogenarians will increase in subsequent years as society ages. We conducted a retrospective observational study in octogenarians operated on with TKA between 2015 and 2019, comparing preoperative and postoperative Knee Society Score (KSS), Knee Society Function Score (KSFS), extension and flexion balance, and radiologic alignment using a paired Student t-test. A chi-squared test was used to correlate mortality with Charlson comorbidities index score and with ASA scale. Kaplan–Meier analysis was performed to calculate patient survival. In this period 36 patients ≥80 years underwent TKA, with a mean age of 81.6 years. Of these, 24 patients (66.7%) were classified as ASA II and 12 (33.3%) as ASA III. Sixteen patients (44.4%) were Charlson 0, 14 (38.9%) Charlson 1, two (5.6%) Charlson 2, and four (11.1%) Charlson 3. KSS, KSFS, flexion and extension range, and radiologic alignment were statistically significant (p < 0.001) when comparing preoperatory and post-operatory data. No correlation (p > 0.05) was found between mortality and ASA or Charlson score. Seven patients (19.4%) suffered a medical complication and two patients experienced surgical complications. Four patient died (11.1%) during follow-up. The mean patient survival was 67.4 months. Patients ≥80 years achieve clinical improvement after TKA. Comorbidities, not age, are the burden for surgery in older patients.

Outcome of Midvastus versus Subvastus Approach in Single Stage Bilateral Total Knee Arthroplasty

Objective: To compare midvastus and subvastus approach regarding operative parameters(lateral retinacular release, operative time, neurovascular injury) and outcome (Knee Society Score, Straight Leg Raise) at 12 weeks in single stage bilateral total knee arthroplasty. Study Design: Randomized clinical trial study Place and Duration of Study: Institute of Orthopaedic Surgery and South City Hospital Karachi from 1st January 2016 to 31st December 2018. Methodology: Fifty two patients of both genders ofmore than 50 years with osteoarthritis grade III or IV and bony changes confirmed by AP and lateral radiographs of knee were included. Patients with previous knee surgeries including high tibial osteotomy, deformities &gt;20°(on mechanical axis), any neuromuscular problem and BMI ≥30 were excluded. Final assessment was done at 12 weeks. Isometric quadriceps strength was assessed by holding of contraction in seconds during the lifting (10cm above the plinth) phase of SLR (patient lying supine).Knee score (preoperative and final follow-up) was performed by Knee Society Score. Results: Thirty five were females and 21 males with mean age 65.3 years (50-78 years). Mean body mass index was 27.8 Kg/m2 (26.4-29.9). In midvastus TKR, the mean operative time was 61.7 minutes (range 52-70) whereas the same was 68.3 minutes (range 58-74) in subvastus TKR with p value 0.002. Rate of lateral retinacular release (LLR) was significantly (p=0.011) different between the midvastus TKR 5 (8.9%) and subvastus TKR 11 (19.6%). Neither group had neurovascular injury or early infection of the knee. Active SLR in subvastus group was achieved in shorter time (mean 3.1 days) as compared to midvastus group (mean 4.7 days). There was no difference (p=0.173) in isometric quadriceps strength at 12 weeks between subvastus TKR (mean 18 seconds) and midvastus TKR (mean 17 seconds). Knee society pain and functional scores were comparable between the two approaches at final follow up. Conclusion: Subvastus exposure has advantage of achieving active straight leg raise earlier while midvastus has lower frequency of lateral retinacular release. No difference in hospital stay and postoperative pain scores. Both subvastus and midvastus approaches are safe and offer comparable Knee Society Score outcomes. Keywords: Midvastus, Subvastus, Total knee arthroplasty, Knee Society Score, Straight leg raise

Application of sliding osteotomy in total knee arthroplasty for patients with extra-articular femoral deformity

In order to observe the clinical effects of sliding osteotomy for patients with severe knee osteoarthritis and varus knee due to complex femoral extra-articular deformity to achieve the medial and lateral soft tissue balancing during total knee arthroplasty. From June 2014 to January 2018, a total of 22 patients with severe knee osteoarthritis and complex extra-articular malformation of femurs were treated with total knee arthroplasty. There were 5 males and 17 females in this group, aged 48 to 76 years old, with an average age of (61.3±13.8) years old. All the patients had varus deformities caused by extra-articular deformities of femur. Hip-knee-ankle(HKA) angle was(158.8±9.7) ° before operation, and the average Knee Society Score (KSS) clinical score was 32.6±6.1;KSS function score was 35.8 ±9.6;the average Hospital for Special Surgical (HSS) score was 39.7±4.6;the average range of motion before operation was (80.6±10.7) °. The mechanical alignment method was used in joint replacement. The flexion space was balanced first. The coronal plane vertical sliding osteotomy was performed on the medial femoral condyle for the imbalance of coronal plane. The sliding distance of the osteotomy block was determined by straightening the gap between the inner and outer sides of the space until the space was balanced. After the separated segments were fixed with several screws, the prosthesis was installed as usual. The wounds of all patients healed in the first stage, and no wound complications occurred. All the 22 patients were followed up, and the duration ranged from 18 months to 3 years with an average of (28.2±10.1) months. X-ray showed that the fracture line disappeared for 2 to 5(3.5±1.5) months without nonunion. HKA angle measured at the latest follow up was (178.8±0.7) °, which wassignificantly different from that before operation. The HSS score was 91.3 ±6.0;KSS clinical score 93.7±3.5;KSS functional score 81.2±6.5;and the average range of motion of knee joint was(121.7±11.6) °, which was statistically significant compared with that before operation. For severe knee osteoarthritis patients with complex femoral extra-articular deformity, sliding osteotomy is performed. For severe varus deformity, downward sliding the medial femoral condyle is performed. The operation is relatively simple and the damage is small. It is easy to achieve the balance of internal and external soft tissue in flexion extension space. The short-term clinical effect is satisfactory.

Primary total knee replacement using dished polyethylene with resected posterior cruciate ligament

&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;The choice between preserving, sacrificing or substituting the posterior cruciate ligament (PCL) is always a controversial topic in total knee replacement (TKR). Dished polyethylene insert with PCL resection enables correction of the commonly present fixed flexion and varus deformities. Additionally, the risk of premature wear of polyethylene is less because of the confirming articular geometry between the femoral and tibial component.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;This is a retrospective study in which we studied 120 knees in 95 consecutive patients undergoing primary TKR by the senior author at our institute. We used TKR system with dished metal backed polyethylene tibial component. PCL resection was performed in all cases. Pre-operative and post-operative functional assessment were done using knee society clinical scores and Western Ontario and McMaster universities osteoarthritis index (WOMAC). All radiographs were assessed using the knee society Roentgenographic scoring system (KSRES). Statistical analysis was performed using paired student t tests. Survivorship was determined using Kaplan-Meier survivorship curves. &lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;Mean follow-up was 8 years. Range of motion increased from 75 degrees to 110 degrees. The knee society pain score increased from 30 to 94. The knee society function score increased from 35 to 75. WOMAC score increased in terms of pain, stiffness and physical function.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;We conclude that deep dish bearing is a viable option in presence of deficient PCL and provides adequate stability and functional outcome. We need a larger sample size, multicentre trial and longer follow-up to see for complication rate, revision rate and survival.&lt;/p&gt;

Defining the minimal clinically important difference for theknee society score following revision total knee arthroplasty.

No previous study has evaluated the MCID for revision total knee arthroplasty (TKA). This study aimed to identify the MCID for the Knee Society Score (KSS), for revision TKA. Prospectively collected data from 270 patients who underwent revision TKA at a single institution was analysed. Clinical assessment was performed preoperatively, at 6months and 2years using Knee Society Function Score (KSFS) and Knee (KSKS) Scores, and Oxford Knee Score (OKS). MCID was evaluated with a three-pronged methodology, using (1) anchor-based method with linear regression, (2) anchor-based method with receiver operating characteristic (ROC) and area under curve (AUC), (3) distribution-based method with standard deviation (SD). The anchors used were improvement in OKS≥5, patient satisfaction, and implant survivorship following revision TKA. The cohort comprised 70% females, with mean age of 69.0years, that underwent unilateral revision TKA. The MCID determined by anchor-based linear regression method using OKS was 6.3 for KSFS, and 6.6 for KSKS. The MCID determined by anchor-based ROC was between 15 and 20 for KSFS (AUC: satisfaction=71.8%, survivorship=61.4%) and between 33 and 34 for KSKS (AUC: satisfaction=76.3%, survivorship=67.1%). The MCID determined by distribution-based method of 0.5 SD was 11.7 for KSFS and 11.9 for KSKS. The MCID of 6.3 points for KSFS, and 6.6 points for KSKS, is a useful benchmark for future studies looking to compare revision against primary TKA outcomes. Clinically, the MCID between 15 and 20 for KSFS and between 33 and 34 for KSKS is a powerful tool for discriminating patients with successful outcomes after revision TKA. Implant survivorship is an objective and naturally dichotomous outcome measure that complements the subjective measure of patient satisfaction, which future MCID studies could consider utilizing as anchors in ROC. II.

Intraoperative rotational kinematics and its influence on postoperative clinical outcomes differ according to age in Unicompartmental knee Arthroplasty

BackgroundAlthough Oxford unicompartmental knee arthroplasty (UKA) is used in patients of wide age ranges, there is no clear information regarding the age differences in terms of intraoperative femorotibial rotational kinematics and its influence on clinical outcomes. Therefore, this study was conducted to examine the age differences in terms of intraoperative rotational kinematics and postoperative clinical outcomes and to analyze their relationship with classification according to the age group.MethodsWe investigated 111 knees of patients who underwent Oxford UKA using a navigation system and divided them into two groups: elderly (aged ≥75 years; 48 knees) and nonelderly (aged < 75 years; 63 knees). Intraoperative tibial internal rotational angles relative to the femur during passive knee flexion were measured using a navigation system, and clinical outcomes were evaluated using knee range of motion, the Knee Injury and Osteoarthritis Outcome Score (KOOS), and the Knee Society Functional Score at 2 years postoperatively. The relationships between intraoperative tibiofemoral rotational angles and clinical outcomes were also evaluated in the two groups.ResultsThe intraoperative tibial internal rotational angle relative to the femur during knee flexion was significantly larger in the nonelderly group (13.5°) than in the elderly group (9.0°). The intraoperative tibial internal rotational angle showed a positive correlation with the pain subscale of KOOS only in the nonelderly group.ConclusionIntraoperative rotational kinematics and its influence on clinical outcomes were different between elderly and nonelderly patients, and the tibial internal rotational angle could be a more important factor for successful UKA in nonelderly patients.

Patient satisfaction following total knee arthroplasty using restricted kinematic alignment.

Alternative alignment concepts, including kinematic and restricted kinematic, have been introduced to help improve clinical outcomes following total knee arthroplasty (TKA). The purpose of this study was to evaluate the clinical results, along with patient satisfaction, following TKA using the concept of restricted kinematic alignment. A total of 121 consecutive TKAs performed between 11 February 2018 to 11 June 2019 with preoperative varus deformity were reviewed at minimum one-year follow-up. Three knees were excluded due to severe preoperative varus deformity greater than 15°, and a further three due to requiring revision surgery, leaving 109 patients and 115 knees to undergo primary TKA using the concept of restricted kinematic alignment with advanced technology. Patients were stratified into three groups based on the preoperative limb varus deformity: Group A with 1° to 5° varus (43 knees); Group B between 6° and 10° varus (56 knees); and Group C with varus greater than 10° (16 knees). This study group was compared with a matched cohort of 115 TKAs and 115 patients using a neutral mechanical alignment target with manual instruments performed from 24 October 2016 to 14 January 2019. Mean overall patient satisfaction for the entire cohort was 4.7 (SE 0.1) on a 5-point Likert scale, with 93% being either very satisfied or satisfied compared with a Likert of 4.3 and patient satisfaction of 81% in the mechanical alignment group (p < 0.001 and p < 0.006 respectively). At mean follow-up of 17 months (11 to 27), the mean overall Likert, Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, Western Ontario and McMaster Universities Osteoarthritis Index, Forgotten Joint Score, and Knee Society Knee and Function Scores were significantly better in the kinematic group than in the neutral mechanical alignment group. The most common complication in both groups was contracture requiring manipulation under anaesthesia, involving seven knees (6.1%) in the kinematic group and nine knees (7.8%) in the mechanical alignment group. With the advent of advanced technology, and the ability to obtain accurate bone cuts, the target limb alignment, and soft-tissue balance within millimetres, using a restricted kinematic alignment concept demonstrated excellent patient satisfaction following primary TKA. Longer-term analysis is required as to the durability of this method. Cite this article: Bone Joint J2021;103-B(6 Supple A):59-66.

No differences in 10-year clinical outcomes and quality of life between patients with different mediolateral femoral component positions in fixed-bearing medial unicompartmental knee arthroplasty.

There has been a paucity of literature evaluating the role of mediolateral femoral component position (FCP) in medial unicompartmental arthroplasty (UKA). Hence, the aim of this study is to evaluate whether the mediolateral FCP in UKA will affect the 10-year clinical outcomes and quality of life of patients who underwent medial UKA. Data of 262 patients who underwent medial UKA were analyzed. All patients were assessed at 6 months, 2 years and 10 years using the Knee Society Function Score, Knee Society Knee Score, Oxford Knee Score, Short-Form 36 Physical/Mental Component Scores and postoperative satisfaction. The mediolateral FCP on postoperative radiographs was measured by independent assessors using the Picture Archiving and Communication Systems. 144 patients were distributed into group C (center), 98 into group M (medial) and 20 into group L (lateral) according to FCP, and one-way ANOVA was used to compare the functional outcomes of the three groups. No statistical differences were found between the three groups in terms of 10-year clinical outcomes, quality of life, satisfaction rates and revision rates. Differences in mediolateral FCP did not result in significant difference in 10-year postoperative clinical outcomes for patients who underwent fixed-bearing medial UKAs. Retrospective study, Level III.

A Complication Profile of Total Hip and Knee Arthroplasty in Liver Transplantation Patients: A Meta-Analysis

BackgroundThere is an increasing demand for total joint arthroplasty in liver transplantation patients. However, significant heterogeneity in existing studies creates difficulty to draw conclusions on the risk profile of arthroplasty in this population. MethodsA systematic review of the literature dated from 1980 to 2020 describing the complication rates of liver transplantation patients receiving either total hip or knee arthroplasty was conducted. Multiple outcomes were extracted and a meta-analysis was performed. Four cohorts were created for analysis purposes: liver transplant patients undergoing THA and TKA (1), THA only (2), TKA only (3), and controls (4). ResultsA total of 13 studies were included in this meta-analysis, accounting for 3024 liver transplantation patients. The rate of infection (odds ratio [OR] = 2.14, OR = 1.61, OR = 2.52), myocardial infarction (OR = 1.65, OR = 1.75, OR = 1.57), respiratory failure (OR = 2.19, OR = 2.50, OR = 1.96), acute kidney injury (OR = 5.71, OR = 5.40, OR = 4.35), sepsis (OR = 3.72, OR = 3.30, OR = 4.02), and blood transfusions (OR = 2.09, OR = 3.65, OR = 1.74) were all significantly higher in the 3 cohorts compared to the controls. Revision/reoperation rates were significantly higher in cohorts 1 and 3 (OR = 1.52 and OR = 1.62, respectively). Patient-reported outcomes saw improvements in Harris Hip Score, objective Knee Society Score, and functional Knee Society Score postoperatively (average improvement = 32.4, 37.2, and 15.3, respectively). ConclusionLiver transplantation patients functionally benefit from total hip and knee arthroplasty, but at the cost of increased risk of infection, revision/reoperation, and medically related complications compared to controls. Mortality may also be a short-term risk.

Preoperative Flexion Contracture Does Not Compromise the Outcomes and Survivorship of Medial Fixed Bearing Unicompartmental Knee Arthroplasty

BackgroundDespite the expanding indications for unicompartmental knee arthroplasty (UKA), the classic indication that limits flexion contracture to <5° in fixed bearing UKA excludes most patients with arthritic knees and has not been challenged in modern literature. This study compared the clinical outcomes between patients with severe flexion contracture and controls undergoing UKA. MethodsEighty seven medial fixed bearing UKAs performed in patients with severe (≥15°) flexion contracture were matched 1:1 with 87 controls without flexion or recurvatum deformity (−5°<extension<5°) using propensity scores to control for age, sex, BMI, Charlson comorbidity index, ASA class, and baseline patient-reported outcome measures (PROMs). Perioperative outcomes were recorded. Range of motion, Knee Society Score, Oxford Knee Score, SF-36, and patient satisfaction were assessed at 6 months and 2 years. Survivorship was recorded at mean 11.5 ± 3.2 years. ResultsPreoperative knee extension in the control and contracture groups was 0.9° ± 1.9° and 18.0° ± 3.5° (P < .001), respectively, whereas flexion was 122.8° ± 27.9° and 120.6° ± 13.6° (P = .502). The contracture group had poorer Knee Society functional (P = .023) and SF-36 physical score (P = .010) at 6 months. However, there was no difference in PROMs at 2 years. A similar proportion achieved the minimal clinically important difference for each PROM and was satisfied with surgery. Range of motion remained poorer in the contracture group and a higher percentage had residual contractures (P < .001). Ten-year survivorship was 94% and 97% in the control and contracture groups, respectively (P = .145). ConclusionAlthough patients with severe flexion contractures had a poorer range of motion and postoperatively, these patients attained comparable PROMs, satisfaction rates, and mid-term survivorship after UKA. Level of EvidenceIII, therapeutic study.

L’articulation fémoro-patellaire n’est pas altérée cliniquement après ostéotomie tibiale de valgisation par ouverture médiale

BackgroundAfter high tibial osteotomy (HTO), the loading of the lateral compartment can be increased. Moreover, the change of patellar height may adversely affect the patellofemoral joint and functional outcomes. HypothesisWe hypothesized that the cartilage of the lateral compartment and patellofemoral joint would worsen after open-wedge HTO and the overcorrection of HTO could worsen the cartilage state of the patellofemoral joint. We evaluated the cartilage status and clinical results after medial open-wedge HTO and the factors affecting the outcomes. Materials and methodsFrom 2011 to 2018, 49 patients who had a mean age of 54.9 years and who underwent medial open-wedge HTO were selected. Plate removal was performed at a mean of 37.0 (range, 13–89) months after HTO, whereas diagnostic arthroscopy was performed during medial open-wedge HTO and plate removal. The cartilage status of each joint and the clinical results, including the Hospital for Special Surgery (HSS) score, Knee Society knee score (KS) and function score (FS), and patellar score, were compared. We evaluated the postoperative changes in the cartilage status and clinical scores. Additionally, we evaluated whether the postoperative correction degree could affect the clinical results. ResultAfter medial open-wedge HTO, the patellar height decreased. There was no change in the cartilage at the patellar and femoral trochlear groove. The HSS score, KS, and FS improved, but the patellar score remained unchanged. In the overcorrection group, the cartilage status significantly deteriorated at the lateral tibia condyle as compared with that in the undercorrection group. Higher preoperative clinical scores were associated with less postoperative improvement. Discussion and conclusionThe outcomes in the patellofemoral joint, including the cartilage condition and clinical scores, did not change after open-wedge HTO, despite patellar infera. Additionally, they were not influenced by the correction degree. Higher preoperative clinical scores were associated with less postoperative improvement. Level of evidenceIV; Retrospective study.

Prospective Mid-Term Results of a Completely Metal-Free Ceramic Total Knee Endoprosthesis: A Concise Follow-Up of a Previous Report

BackgroundHypersensitivity reactions are suspected to cause premature aseptic loosening in susceptible patients after total knee arthroplasty. In response, metal-free implants have been developed. The aim of this prospective, observational midterm study was the assessment of a completely metal-free ceramic knee replacement system as a concise follow-up of a previous report. MethodsThirty-eight patients, with anamnestic suspected or documented allergy to the metal used in prosthetic alloys, participated in this 4-year follow-up of the metal-free BPK-S (Peter Brehm) total knee replacement system with ceramic femoral and tibial components. Clinical assessment included Knee Society Score (KSS), Oxford Knee Score, Euro Quol-5D-Visual Analogue Scale (EQ-5D-VAS), and perioperative or postoperative complications and need for revision. The position of the implant, signs of loosening, and leg alignment were assessed radiographically. ResultsAll postoperative clinical scores improved significantly from baseline to 48-month follow-up examination. The Oxford Knee Score improved from 39 to 15 points. The KSS improved from 99 to 195 points (the KSS knee score 42.5 to 96 and the KSS function score 60 to 100). The EQ-5D improved from 12 to 7 points; the EQ-VAS improved from 52.5 to 97 points. No allergic reactions could be detected. Radiologically, a median preoperative varus deformity of 5° improved to 0° at 4-year follow-up. Radiolucent lines appeared around uncemented areas with no clinical symptoms. ConclusionThe fully metal-free BPK-S Integration ceramic knee replacement system exhibits excellent immuno-allergological compatibility, offering a safe option for patients with prior hypersensitivity reactions to metallic materials. Full cementation of all components is recommended to avoid radiolucent lines around the implant.