Predictive factors for deep medial collateral ligament release in adjusted mechanical alignment total knee arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) demands precision in achieving optimal alignment and soft tissue balance, especially in cases of medial compartment osteoarthritis where the need for medial soft tissue release is critical yet challenging to ascertain. OBJECTIVE: This study aims to systematically investigate the relationship between preoperative data, initial knee conditions and the necessity for deep collateral ligament (MCL) release in adjusted mechanical alignment total knee arthroplasty. METHODS: We conducted a retrospective study involving 61 TKA patients who underwent adjusted mechanical alignment robotic-assisted procedures. Soft tissue release was carried out when clinically indicated. We collected and statistically analyzed patient demographics, initial knee conditions, and surgical details. RESULTS: Among the patients, 52% required deep MCL release. Notably, patients without soft tissue release exhibited lower initial hip-knee-ankle (HKA) angles, reduced varus-valgus stress test angles, and a greater range of flexion. We identified a predictive threshold HKA angle of 6.250 degrees, demonstrating high sensitivity and specificity for determining the need for deep MCL release. CONCLUSION: This study underscores the significance of the initial HKA angle and varus-valgus stress tests in predicting deep MCL release during TKA. The established HKA angle threshold simplifies surgical decision-making, reducing the likelihood of unnecessary soft tissue release.

Comparison of early curative effects of lateral unicompartmental knee arthroplasty with total knee arthroplasty and the legacy constrained condylar knee arthroplasty in the treatment of isolated lateral osteoarthritis: a single-center retrospective study.

BACKGROUND: Aims of this study were to compare the functional and radiographic results, perioperative complication after lateral unicompartmental knee arthroplasty (LUKA) with total knee arthroplasty (TKA) and the legacy constrained condylar knee (LCCK) arthroplasty for the treatment of lateral compartmental knee osteoarthritis (LCKOA), and to provide a basis for the treatment of LCKOA. METHODS: From January 2021 to January 2024, analyzed retrospectively clinical data of 74 patients with LCKOA treated with LUKA, TKA and LCCK arthroplasty. According to the operation plan, the patients were divided into three groups: LUKA group (23 cases), TKA group (23 cases) and LCCK group (28 cases). The changes of hip-knee-ankle (HKA) angle of the affected knee before and after operation were measured. All patients were assessed using the operation time, blood loss during operation, incision length, visual analogue scale (VAS) score before operation and after operation, Hospital for Special Surgery score (HSS), Oxford Knee Score (OKS), range of motion (ROM). RESULTS: All 74 patients were followed up for (2.38 ± 0.33) years. The operation time, blood loss during operation, incision length and VAS score after operation in the LUKA group were significantly less than those in the TKA group and LCCK group (P < 0.05); HKA valgus angle, ROM, HSS score and OKS score of the three groups after operation were significantly better than those before operation (P < 0.05); There was no significant difference among the three groups in HSS score and OKS score (P > 0.05). CONCLUSION: LUKA, TKA and LCCK arthroplasty have good clinical effect in the treatment of LCKOA; Compared with TKA and LCCK arthroplasty, LUKA has the advantages of less trauma, less bleeding, less pain and quick recovery. The short-term effect is satisfactory, and the long-term effect remains to be observed.

A high-flexion design total knee prosthesis: a ten to twelve-year follow-up study.

BACKGROUND: The purpose of this study was to investigate the clinical and radiographic outcomes and to determine the survivorship of a high-flexion design total knee arthroplasty (TKA) prosthesis, the LOSPA knee system, over a follow-up period of 10-12 years. METHODS: The study included 386 patients (503 TKAs) who were treated with TKA from 2011 to 2013 (follow-up period 10-12 years).The patients were assessed clinically using range of motion (ROM) of the knee, the Knee Society scoring system (KSS), and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). For radiographic analysis, the positions of femoral and tibial implants as α, ß, γ, and δ angles, hip knee ankle (HKA) angle, and radiolucent lines were used. Kaplan-Meier survival analysis was performed. RESULTS: Mean ROM improved significantly from the preoperative baseline of 117.3° to 126.5° at the final follow-up (p < 0.001). The mean KSS and WOMAC scores also both showed significant improvement after surgery (all p < 0.001). A non-progressive radiolucent line less than 2 mm was observed in 23 cases (4.7%). Nine patients underwent revision surgery on the knee during the follow-up period. Revision surgery was performed on four patients due to aseptic loosening, three patients due to infection, one patient due to ankylosis, and one patient due to instability. When the endpoint of survival was the entire surgical cases, the survival rate was 96.2%. The survival rate, with revision for any reason as the endpoint, was 97.2%, and 97.8% for aseptic causes. CONCLUSIONS: The LOSPA knee system, a high-flexion design total knee prosthesis, showed excellent long-term survivorship and improvements in clinical outcomes at 10- to 12-year follow-up.

[Early gait analysis after total knee arthroplasty based on artificial intelligence dynamic image recognition].

OBJECTIVE: To explore early postoperative gait characteristics and clinical outcomes after total knee arthroplasty (TKA). METHODS: From February 2023 to July 2023, 26 patients with unilateral knee osteoarthritis (KOA) were treated with TKA, including 4 males and 22 females, aged from 57 to 85 years old with an average of (67.58±6.49) years old;body mass index (BMI) ranged from 18.83 to 38.28 kg·m-2 with an average of (26.43±4.15) kg·m-2;14 patients on the left side, 12 patients on the right side;according to Kellgren-Lawrence(K-L) classification, 6 patients with grade Ⅲ and 20 patients with grade IV;the courses of disease ranged from 1 to 14 years with an average of (5.54±3.29) years. Images and videos of standing up and walking, walking side shot, squatting and supine kneeling were taken with smart phones before operation and 6 weeks after operation. The human posture estimation framework OpenPose were used to analyze stride frequency, step length, step length, step speed, active knee knee bending angle, stride length, double support phase time, as well as maximum hip flexion angle and maximum knee bending angle on squatting position. Western Ontario and McMaster Universities (WOMAC) arthritis index and Knee Society Score (KSS) were used to evaluate clinical efficacy of knee joint. RESULTS: All patients were followed up for 5 to 7 weeks with an average of (6.00±0.57) weeks. The total score of WOMAC decreased from (64.85±11.54) before operation to (45.81±7.91) at 6 weeks after operation (P<0.001). The total KSS was increased from (101.19±9.58) before operation to (125.50±10.32) at 6 weeks after operation (P<0.001). The gait speed, stride frequency and stride length of the affected side before operation were (0.32±0.10) m·s-1, (96.35±24.18) steps·min-1, (0.72±0.14) m, respectively;and increased to (0.48±0.11) m·s-1, (104.20±22.53) steps·min-1, (0.79±0.10) m at 6 weeks after operation (P<0.05). The lower limb support time and active knee bending angle decreased from (0.31±0.38) s and (125.21±11.64) ° before operation to (0.11±0.04) s and (120.01±13.35) ° at 6 weeks after operation (P<0.05). Eleven patients could able to complete squat before operation, 13 patients could able to complete at 6 weeks after operation, and 9 patients could able to complete both before operation and 6 weeks after operation. In 9 patients, the maximum bending angle of crouching position was increased from 76.29° to 124.11° before operation to 91.35° to 134.12° at 6 weeks after operation, and the maximum bending angle of hip was increased from 103.70° to 147.25° before operation to 118.61° to 149.48° at 6 weeks after operation. CONCLUSION: Gait analysis technology based on artificial intelligence image recognition is a safe and effective method to quantitatively identify the changes of patients' gait. Knee pain of KOA was relieved and the function was improved, the supporting ability of the affected limb was improved after TKA, and the patient's stride frequency, stride length and stride speed were improved, and the overall movement rhythm of both lower limbs are more coordinated.

[A retrospective study on two different surgical robots to assist total knee arthroplasty].

OBJECTIVE: To compare early clinical and imaging results of domestic HURWA and imported Brainlab Knee3 surgical robot-assisted knee replacement. METHODS: A retrospective analysis was performed on 93 patients with knee osteoarthritis (KOA) who underwent robot-assisted descending total knee arthroplasty(TKA) from January 2021 to July 2023, and they were divided into BRATKA group and HRATKA group according to use of robotic system. There were 40 patients in BRATKA group, including 16 males and 24 females, aged from 55 to 90 years old with an average of (64.3±7.0) years old;27 patients with grade Ⅲ and 13 patients with grade Ⅳ according to Kellgren-Lawrence(K-L);18 patients on the right side and 22 patients on the left side;the courses of disease ranged from 1 to 30 years with an average of (15.3±7.6) years;imported Brainlab Knee3 surgical robot assisted system was adopted. There were 53 patients in HRATKA group, including 18 males and 35 females, aged from 52 to 81 years old with an average of (64.4±8.5) years old;30 patients with grade Ⅲ and 23 patients with grade Ⅳ;21 patients on the right side and 32 patients on the left side;the courses of disease ranged from 1 to 32 years with an average of (16.4±7.9) years;HURWA surgical robot assisted system was adopted. Operation time, perioperative total blood loss, incision length and postoperative complications were compared between two groups. Deviation angle of hip-knee-ankle angle(HKAA) before operation and on the first day after operation was compared between two groups. Later tibal component (LTC), frontal femoral component (FFC), later femoral component (LFC) and frontal tibal component(FTC) at 1 day after on the first day after operation was compared between two groups. Knee Society score(KSS), visual analogue scale (VAS) and range of motion (ROM) of knee joint were compared between two groups before operation and on the 3rd and 90th day after operation. RESULTS: Both groups were followed up for 11 to 18 months with an average of (14.4±2.1) months, and the wounds of all patients healed well. Operation time and incision length of BRATKA group were (132.1±34.6) min and (12.9±1.9) cm, while (94.1±10.8) min and (14.8±2.1) cm in HRATKA group, respectively, and the differences between two groups were statistically significant(P<0.05). There were no significant difference in perioperative total blood loss and preoperative deviation angle of HKAA between two groups(P>0.05). Deviation angle of HKAA, FFC angle and LFC angle in BRATKA group were (1.90±0.91) °, (87.90±1.51) ° and(9.00±3.2) °, respectively;while (0.93±1.04) °, (89.03±0.96) ° and (7.63±0.59) ° in HRATKA group, respectively, and the differences between two groups were statistically significant (P<0.05). There were no significant differences in FTC and LTC between two groups(P>0.05). There were no significant differences in VAS of knee rest and exercise, KSS score and ROM of knee joint between two groups before operation and 3 days and 90 days after operation(P>0.05). There was no significant difference in complications between two groups (P>0.05). CONCLUSION: Postoperative imaging of two robot systems showed good lower limb force line. The domestic HRATKA group had better LFC, FFC angle and HKA deviation angle than the imported BRATKA group, but there were no significant difference in postoperative knee function and pain relief.

[Comparative study of total knee arthroplasty assisted by robot and remote sensing navigation system].

OBJECTIVE: To compare clinical efficacy of robot-assisted (RA) and remote sensing navigation alignment (RSNA) system-assisted total knee arthroplasty (TKA). METHODS: From March 2023 to June 2023, 60 patients who underwent the first unilateral TKA due to severe knee osteoarthritis (KOA) were admitted and divided into RSNA group and RA group according to different treatment methods, with 30 patients in each group. There were 5 males and 25 females in RSNA group, aged from 56 to 81 years old with an average of(66.33±7.16) years old;body mass index(BMI) ranged from 19.87 to 38.54 kg·m-2 with an average of (28.40±6.18) kg·m-2;the courses of disease ranged from 5 to 36 months with an average of (18.20±8.98) months; RSNA system was used to assist the positioning of osteotomy. There were 7 males and 23 females in RA group, aged from 55 to 82 years old with an average of (67.83±8.61) years old;BMI ranged from 19.67 to 37.25 kg·m-2 with an average of (28.01±4.89) kg·m-2; the courses of disease ranged from 3 to 33 months with an average of (17.93±9.20) months;RA was performed. Operation time, incision length, latent blood loss at 2 weeks after operation and incidence of lower extremity thrombosis were compared between two groups. Hip-knee ankle angle (HKAA), HKAA deviation, lateral distal femoral angle ( LDFA), medial proximal tibial angle (MPTA) and posterior tibial slope (PTS) were compared between two groups;Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) and Knee Society score (KSS) were used to evaluate functional recovery before operation, 3 and 6 months after operation. RESULTS: The operation was performed successfully in both groups, and there were no serious complications such as vascular and nerve injury during operation. The wound healed well at stageⅠafter operation, and the follow-up time was 6 months. The operation time, latent blood loss at 2 weeks after operation and incision length in RSNA group were (94.35±5.75) min, (130.54±17.53) ml and (14.73±2.14) cm, respectively;while (102.57±6.88) min, (146.33±19.47) ml and (16.78±2.32) cm in RA group, respectively. RSNA group was better than RA group (P<0.05). No deep vein thrombosis occurred in both groups at 2 weeks after operation, 5 patients occurred intermuscular vein thrombosisin in RSNA group and 8 patients in RA group, the difference was not statistically significant (P>0.05). In RSNA group, HKAA, LDFA and MPTA were (173.00±5.54) °, (86.96±3.45) °, (82.79±3.35) ° before operation, and (178.34±1.85) °, (89.92±0.42) °, (89.84±0.73) ° at 1 week after operation, respectively. In RA group, HKAA, LDFA and MPTA were (173.31±6.48) °, (87.15±3.40) ° and (82.99±3.05) ° before operation, and (178.52±1.79) °, (90.03±0.39) ° and (90.15±0.47) ° at 1 week after operation, respectively. HKAA, LDFA and MPTA were significantly improved in both groups at 1 week after operation (P<0.05). There were no significant difference in HKAA, LDFA, MPTA and PTS between two groups before operation and 1 week after operation (P>0.05). There was no significant difference in deviation distribution of HKAA at 1 week after operation (χ2=2.611, P=0.456). There were no significant difference in WOMAC and KSS between two groups before operation, 3 and 6 months after operation (P>0.05), and postoperative WOMAC and KSS at 3 and 6 months between two groups were improved compared with those before operation (P<0.05). CONCLUSION: Both RA and RSNA system assisted TKA could obtain accurate osteotomy, RA has higher surgical accuracy, RSNA system assisted operation has less trauma, and operation is simpler.

[Application of remote sensing navigation system in total knee arthroplasty].

OBJECTIVE: To explore clinical accuracy of remote sensing navigation alignment (RSNA) system in total knee arthroplasty (TKA) and its influence on postoperative clinical efficacy. METHODS: From May 2021 to May 2022, 60 knee osteoarthritis (KOA) patients with Kellgren-Lawrence (K-L) grade Ⅲ to Ⅳ treated by unilateral primary TKA were selected and divided into RSNA group and traditional operation group according to treatment methods, and 30 patients in each group. There were 6 males and 24 females in RSNA group, aged from 55 to 86 years old with an average of (68.06±8.23) years old;body mass index (BMI) ranged from 22.15 to 34.58 kg·m-2 with an average of (28.20±3.01) kg·m-2;the courses of disease ranged from 2 to 60 months with an average of (18.80±14.80) months;13 patients with grade Ⅲ and 17 patients with grade Ⅳ according to K-L grading. In traditional operation group, there were 8 males and 22 females, aged from 57 to 85 years old with an average of (67.26±6.32) years old;BMI ranged from 23.94 to 34.55 kg·m-2 with an average of (27.49±2.32) kg·m-2;the courses of disease ranged from 3 to 60 months with an average of (21.30±16.44) months;14 patients with grade Ⅲ and 16 patients with grade Ⅳ according to K-L grading. Western Ontario and McMaster Universities (WOMAC) osteoarthritis index and Knee Society score(KSS) were used to evaluate functional recovery of patients. Hip-knee-ankle angle (HKAA), distal femoral valgus angle (FVA) and distal fermoral flexion angle (DFFA) were measured before operation. HKAA and HKAA deviation angle were measured at 1 week after operation, and defective rate of lower limb force line, femur prosthesis valgus angle (FPVA) and femoral prosthesis flexion angle (FPFA), respectively, were calculated. RESULTS: There were no serious complications such as vascular and nerve injury during operation, and wound healed at stage Ⅰ. Both groups were followed up for 6 months. There were no significant difference in WOMAC index, KSS, HKAA, FVA and DFFA between two groups before operation (P>0.05). The force line defect rate, HKAA, HKAA deviation angle, FPVA deviation angle and FPFA of RSNA group were 6.7%, (178.74±1.56) °, (1.25±1.56) °, (1.84±0.16) ° and (4.85±2.46) °, respectively;while in traditional operation group were 20%, (176.73±3.46) °, (3.27±3.46) °, (2.44±0.26) °, (6.60±1.86) °;the difference between two groups were statistically significant (P<0.05). There were no significant difference in WOMAC index and KSS between two groups at 3 and 6 months after operation (P>0.05). CONCLUSION: RSNA system could reduce defective rate of lower limb force line, FPVA deviation angle and FPFA after TKA, which is more accurate and easy to operate than traditional intramedullary localization surgery while ensuring postoperative efficacy.

No single safe zone exists for the valgus cut angle to reproduce neutral mechanical alignment in the presence of femoral bowing in total knee arthroplasty.

PURPOSE: The aim of this study is to report the prevalence of femoral bowing in the Egyptian arthritic knees as a representative of the middle eastern population and to study the correlation between the femoral bowing and the degree of arthritis, varus deformity and the distal femoral valgus cut angle (VCA). METHODS: This is a single-center observational cross-sectional study. Out of 562 knees Scheduled for TKA, 124 knees were excluded leaving 438 knees eligible for the study. The following angles were measured by two independent orthopedic surgeons: Femoral bowing angle (FBA), HKA angle, LDFA, MPTA and VCA. RESULTS: Out of 438 knees, 21knees (4.8%) had medial bowing (< - 3°), 111 (25.3%) had normal bowing (+ 3° to - 3°) and 306 (69.9%) had LFB of which 111 (25.34%) had mild LFB (+ 3 to + 5°) and 195 (44.52%) had severe LFB (> + 5°) bowing. LFB was more in older age group (p = 0.005), in females (p < 0.001), and in grade 4 OA, (p < 0.001). Also, there was a significant positive correlation between FBA and age and increasing varus HKA, and with varus orientation of the distal femur and the tibial plateau. The mean and the 95% confidence interval of the VCA for the medial bowing group was 3.43 (3.01-3.85°), for the normal bowing group was 5.42 (5.15-5.68°), for the mild lateral bowing was 6.74 (6.47-7°), and for the severe bowing group was 9.23 (8.89-9.55°). CONCLUSIONS: There is no single safe zone for the VCA to reproduce postoperative neutral coronal alignment especially in cases of severe lateral femoral bowing in TKA. However, the VCA should be analyzed in term of how much femoral bowing exists. In other words, for each subset of femoral bowing there is a safe zone for the VCA.

Cemented versus cementless Oxford unicompartmental knee arthroplasty for the treatment of medial knee osteoarthritis: an updated systematic review and meta-analysis.

OBJECTIVE: This meta-analysis sought to compare the efficacy of cemented versus cementless Oxford unicompartmental knee arthroplasty(UKA) for the treatment of medial knee osteoarthritis. METHODS: A comprehensive search of the following databases was conducted: Pubmed, The Cochrane Library, China National Knowledge Infrastructure (CNKI), Embase, the Web of Science, and MEDLINE. The objective was to identify literature comparing cemented versus cementless Oxford unicompartmental knee arthroplasty for the treatment of medial knee osteoarthritis. Duplicate literature, low-quality literature, literature with incompatible observations, and literature for which the full text was not available were excluded. Two independent researchers employed the Cochrane Risk Assessment Tool and the Newcastle-Ottawa Scale (NOS) to evaluate the quality of the included literature. The data then were extracted and subsequently meta-analyzed using RevMan 5.4. RESULTS: A total of 12 papers were included in the analysis, encompassing a cumulative of 2558 cumulative cases. Of these, 1258 were cemented and 1300 were cementless. A meta-analysis was conducted to compare the outcomes of cemented versus cementless Oxford UKA. The Oxford UKA group exhibited a significantly longer surgery time than the cementless Oxford UKA group [mean difference (MD) = 9.91, 95% confidence interval (CI) (7.64,12.17)]. Additionally, the cemented Oxford UKA group demonstrated a significantly lower knee OKS score compared to the cementless Oxford UKA group. The mean difference (MD) was - 1.58 (95% CI: -2.30, -0.86), indicating a significantly lower score for the cemented Oxford UKA group. Similarly, the mean difference (MD) was - 1.8 for the knee KSS clinical score, indicating a significantly lower score for the cemented Oxford UKA group. The results demonstrated that the knee KSS functional score was significantly lower in the cemented Oxford UKA group than in the cementless Oxford UKA group [MD=-1.72, 95% CI (-3.26, -0.37)]. 95% CI (-3.27,-0.17)], the cemented Oxford UKA group exhibited a significantly higher incidence of radiolucent lines around the prosthesis than the cementless Oxford UKA group [ratio of ratios (OR) = 3.62, 95% CI (1.08,12.13)]. The revision rate was significantly higher in the cemented Oxford UKA group than in the cementless Oxford UKA group [OR = 2.22, 95% CI (1.40,3.53)]. However, no significant difference was observed between the two groups in terms of reoperation rate, five-year prosthesis survival rate, and complication rate. CONCLUSIONS: The findings indicated that, in comparison to cemented Oxford UKA, cementless Oxford UKA resulted in a reduction in surgical time, an improvement in knee OKS score, KSS clinical score, and KSS functional score, and a decrease in the incidence of periprosthetic radiolucent lines and the rate of revisions.

No shortening of the patellar tendon during two-stage total knee arthroplasty revision using articulating spacers.

BACKGROUND: Surgical techniques in two-stage revision total knee arthroplasty (rTKA) include the use of articulating spacers and static spacers. Shortening of the patellar tendon could be a reason for inferior functional outcomes in two-stage septic rTKA . The aim of this study was to determine if articulating spacers also have negative effects on the extensor mechanism in rTKA. METHODS: This retrospective study includes 65 consecutive patients (23 women, 42 men, age 71.3 ± 1.2; range, 51.2-88.6 years) undergoing septic two-stage rTKA using an articulating spacer between 2014 and 2021 in a single orthopedic center. For all patients, calibrated true lateral radiographs before total knee arthroplasty (TKA) explantation (T0), directly after TKA explantation (T1), shortly before TKA reimplantation (T2) and 6-8 days after TKA reimplantation (T3) were used to calculate the modified Insall Salvati ratio (mISR). RESULTS: Overall, the mISR decreased significantly immediately after explantation (T0 vs. T1, p = 0.002) from 1.43 ± 0.03 to 1.36 ± 0.03 and remained stable until T2 (1.37 ± 0.02, p = 0.74). Following TKA reimplantation, the mISR increased again to 1.43 ± 0.03 (T3). There were no significant differences between T0 and T3 (p = 0.88). Six out of 65 patients (9%) experienced patellar tendon shortening > 10% at T3. CONCLUSIONS: Septic two-stage revision TKA using an articulating spacer does not lead to patellar tendon shortening in the majority of cases. This study suggests that one reason for the improved range of motion after reimplantation may be the use of articulating spacers compared to static spacers.

Does patient-specific instrument or robot improve imaging and functional outcomes in unicompartmental knee arthroplasty? A bayesian analysis.

INTRODUCTION: This study conducted a Bayesian network meta-analysis (NMA) to compare the imaging and functional outcomes of patient-specific instrument-assisted unicompartmental knee arthroplasty (P-UKA), robot-assisted unicompartmental knee arthroplasty (R-UKA), and conventional unicompartmental knee arthroplasty (C-UKA). MATERIALS AND METHODS: A comprehensive search was performed on five electronic databases and major orthopedic journals as of September 24, 2023. We included randomized controlled studies featuring at least two interventions of P-UKA, R-UKA, or C-UKA. Primary outcomes encompassed the deviation angle of hip-knee-ankle angle, as well as the coronal and sagittal plane alignment of femoral and tibial components. Secondary outcomes included patient-reported outcome measures (PROM), surgery time, revision rate, and complication rate. Bayesian framework was employed for risk ratio (RR) or mean deviation (MD) analysis, and treatment hierarchy was established based on rank probabilities. RESULTS: This NMA included 871 knees from 12 selected studies. In sagittal plane, R-UKA exhibited a significantly reduced deviation angle of femoral component compared to P-UKA (MD: 4.16, 95% CI: 0.21, 8.07), and of tibial component in comparison to C-UKA (MD: -2.45, 95% CI: -4.20, -0.68). Notably, the surgery time was significantly longer in R-UKA than in C-UKA (MD: 15.98, 95% CI: 3.11, 28.88). However, no significant differences were observed in other outcomes. CONCLUSION: Compared with P-UKA or C-UKA, R-UKA significantly improves the femoral and tibial component alignment in the sagittal plane, although this does not translate into discernible differences in functional outcomes. Comprehensive considerations of economic and learning costs are imperative for the judicious selection of the appropriate procedure.

Changed resting-state connectivity of anterior insular cortex affects subjective pain reduction after knee arthroplasty: A longitudinal study.

The mechanism of chronic knee osteoarthritis (OA) pain and postoperative pain due to knee arthroplasty has not been elucidated. This could be involved neuroplasticity in brain connectivity. To clarify the mechanism of chronic knee OA pain and postoperative pain, we examined the relationship between resting-state functional connectivity (rs-FC) and clinical measurements in knee OA before and after knee arthroplasty, focusing on rs-FCs with the anterior insular cortex (aIC) as the key region. Fifteen patients with knee OA underwent resting-state functional magnetic resonance imaging and clinical measurements shortly before and 6 months after knee arthroplasty, and 15 age- and sex-matched control patients underwent an identical protocol. Seed-to-voxel analysis was performed to compare the clinical measurements and changed rs-FCs, using the aIC as a seed region, between the preoperative and postoperative patients, as well as between the operative and control patients. In preoperative patients, rs-FCs of the aIC to the OFC, frontal pole, subcallosal area, and medial frontal cortex increased compared with those of the control patients. The strength of rs-FC between the left aIC and right OFC decreased before and after knee arthroplasty. The decrease in rs-FC between the left aIC and right OFC was associated with decreased subjective pain score. Our study showed a correlation between longitudinally changed rs-FC and clinical measurement before and after knee arthroplasty. Rs-FC between the aIC and OFC have the potential to elucidate the mechanisms of knee OA pain and postoperative pain due to knee arthroplasty.

[Unicondylar knee arthroplasties demonstrate a significantly increased risk of aseptic revisions compared with unconstrained and constrained TKA : Analysis of aseptic revisions after unicondylar and primary total knee arthroplasty of the German Arthroplasty Register]. / Unikondyläre Knieendoprothesen zeigen ein signifikant erhöhtes Risiko für aseptische Revisionen im Vergleich zu ungekoppelten und gekoppelten TKA : Eine Analyse von aseptischen Revisionen nach unikondylärer und primärer totaler Knieendoprothetik des Endoprothesenregisters Deutschland (EPRD).

OBJECTIVE: Owing to the ageing population the implantation rate of total knee arthroplasty (TKA) continues to rise. Aseptic revisions in primary TKA are one of the main causes of revision. The aim of the following study was to determine the incidence of and reasons for aseptic revision in constrained and unconstrained TKA and in unicondylar knee arthroplasty (UKA). METHODS: The data collection was carried out with the help of the German Arthroplasty Register (EPRD). The reasons for aseptic revision surgery were worked out using this. The incidence and the comparison of aseptic revisions were analysed with the aid of Kaplan-Meier estimates. A multiple Chi-squared test with the Holm method was used to identify group differences in collateral ligament deficiencies. RESULTS: In total, 300,998 cases of knee arthroplasties were analysed, of which 254,144 (84.4%) were unconstrained TKA, 9993 (3.3%) were constrained TKA and 36,861 (12.3%) were UKA. The rate of aseptic revisions was significantly increased compared with unconstrained and constrained TKA (p < 0.0001). In constrained TKA, a revision rate of 2.0% for aseptic reasons was reported, whereas in unconstrained TKA 1.1% and in UKA 2.7% revision surgeries were identified. After 7 years the rates of aseptic revisions amounted to 3.3% for constrained TKA, 2.8% for unconstrained TKA and 7.8% for UKA. Ligament instability was the most common cause of aseptic revisions and accounted for 13.7% of unconstrained TKA. In constrained TKA ligament instability led to a revision in 2.8% of cases. In UKA, tibial loosening was identified to be the most common cause of revisions at 14.6%, whereas the progression of osteoarthritis was responsible for 7.9% of revisions. Ligament instability was observed in 14.1% of men compared with 15.9% of women in unconstrained TKA and in UKA in 4.6% of cases for both sexes. CONCLUSION: In patients with UKA the rates of aseptic revision are significantly higher than in unconstrained and constrained TKA. Ligament instability was the most common cause of aseptic revision in unconstrained TKA. In UKA, tibial loosening was the most common cause of revision surgery, whereas the progression of osteoarthritis was the second most common cause. Comparable levels of ligament instability were observed in both sexes. LEVEL OF EVIDENCE:  III, cohort study.

Effect of tibia-first, restricted functional alignment technique on gap width changes, and component positioning in robotic arm-assisted total knee arthroplasty.

PURPOSE: This study aims to quantitatively assess the predictability of post-resection gap dimensions and the attainment of balanced gaps using robotic arm-assisted total knee arthroplasty (TKA). METHODS: This retrospective cohort study included 100 consecutive patients who underwent robotic arm-assisted TKA for knee osteoarthritis using a restricted functional alignment (FA) technique. Tibial cuts were performed based on preoperative tibial anatomy within predefined boundaries, followed by femoral component adjustments according to tensioned soft tissues to optimise gap balance. The primary outcome was the proportion of balanced gaps, defined as differential laxities of ≤2 mm, across extension, flexion, lateral, and medial gap measurements. Ligament balancing in lateral and medial compartments was assessed using a robotic system at 10° and 90° flexion to evaluate if restricted FA facilitated a balanced knee. Secondary outcomes included implant alignment, resection depth, and patient-reported outcome measures (PROMs). RESULTS: Significant increases in both lateral and medial gaps at 10° and 90° flexion were observed following tibial and femoral bone resections (p < 0.001). At extension, average gap changes were 0.9 mm (lateral) and 1.6 mm (medial) after tibial cuts, and 0.5 mm (lateral) and 1.2 mm (medial) after femoral cuts. At 90° flexion, changes were 0.3 mm (lateral) and 1.7 mm (medial) following tibial cuts, and 1.0 mm (lateral) and 1.4 mm (medial) after femoral cuts. Despite these variations, the tibia-first, gap-balancing technique achieved overall balance in 98% of gap measurements. The tibial component was placed at an average of 2.1° varus, while the femoral component was positioned at 0.3° varus and 1.3° external rotation relative to the surgical transepicondylar axis. Significant improvements in PROMs were noted between preoperative and one-year postoperative evaluations (all p < 0.05). CONCLUSIONS: The tibia-first, restricted FA technique achieved a well-balanced knee in 98% of cases, despite inconsistent gap increments observed between initial assessments and post-resection. LEVEL OF EVIDENCE: Therapeutic Level IV.

Do modifiable patient factors increase the risk of postoperative complications after total joint arthroplasty?

INTRODUCTION: Numerous studies demonstrate that modifiable lifestyle risk factors can influence patient outcomes including survivability, quality of life, and postoperative complications following orthopaedic surgery. The purpose of this study was to determine the impact of modifiable lifestyle risk factors on postoperative medical and surgical complications following a total joint arthroplasty (TJA) in a large national healthcare system. METHODS: A retrospective chart review of a large national health system database was performed to identify patients who underwent TJA between 2017 and 2021. TJA included total knee arthroplasty, total hip arthroplasty, and total shoulder arthroplasty. Modifiable lifestyle risk factors were defined as tobacco use, narcotic drug abuse, hypertension, and diabetes mellitus. Postoperative medical complications and postoperative surgical complications were collected. Logistic regression and odds ratio point estimate analysis were conducted to assess for associations between postoperative complications and modifiable lifestyle risk factors. RESULTS: Of the 16,940 patients identified, the mean age was 71 years, mean BMI was 29.7 kg/m2, and 62% were women. We found that 3.5% had used narcotics, 8.7% were past or current smokers, 24% had diabetes, and 61% had hypertension; in addition, 5.4% experienced postoperative medical complications and 6.4% experienced postoperative surgical complications. Patients who used narcotics were 90% more likely to have postoperative complications (p < 0.0001) and 105% more likely to experience prosthetic complications (p < 0.0001). Similarly, patients with tobacco use were 65% more likely to have postoperative complications (p < 0.0001) and 27% more likely to experience prosthetic complications. CONCLUSIONS: Our results demonstrate critical rates of increased postoperative medical and surgical complications after TJA for patients with narcotic abuse, tobacco use, or diabetes mellitus. Furthermore, adopting preoperative interventions and optimization programs informed by our findings on specific modifiable risk factors could aid orthopaedic surgeons in optimizing patient health. LEVEL OF EVIDENCE: III; Retrospective study.

Does the use of topical vancomycin during primary hip or knee arthroplasty protect from infections?

BACKGROUND: Infection is one of the main complications of hip and knee arthroplasties. Topical application vancomycin to prevent postoperative infections is efficient in spine surgery, and is spreading in prosthetic surgery. However, its clinical relevance and safety are still under debate. Thus, we conducted the present study to (1) assess whether topical vancomycin reduces peri-prosthetic infection rate, and (2) investigate its influence on surgical wound complications. HYPOTHESIS: Our hypothesis was that topical administration of diluted vancomycin during arthroplasty would reduce infection rate within the first postoperative year. MATERIAL AND METHODS: In total, 1900 hip and knee arthroplasties were performed between 2014 and 2021 in a single hospital. From July 2018 and December 2021, 910 prostheses were implanted with intra-articular instillation of vancomycin and tranexamic acid. From November 2014 to June 2018, 990 prostheses were set up without vancomycin. During a follow-up of minimum 12 months, we reported periprosthetic infections occurring during the first postoperative year, as well as vancomycin-induced general or cutaneous complications. RESULTS: We observed periprosthetic infections in 9/990 cases (0.91%) of the control group and 10/910 cases (1.1%) of the vancomycin group (p = 0.82). In parallel, we observed wound complications (erythema, seroma, hematoma, dehiscence and delay in wound healing) in 19/990 (1.9%) and 10/910 cases (1.1%) of the control and vancomycin group, respectively (p = 0.19). There were no general complications resulting from the application of vancomycin. DISCUSSION: Topical diluted vancomycin does not reduce periprosthetic infection risk, and has no effect on the occurrence of surgery wound complications. Considering the present findings, the use of vancomycin cannot be recommended in current practice to prevent infections following hip and knee arthroplasties. Finally, its use does not induce any specific complications, whether local (cicatrisation) or general (related to ototoxicity or nephrotoxicity). LEVEL OF EVIDENCE: III; case control study.

Intraoperative Discovery of Lymphoma in the Knee During a Total Knee Arthroplasty: A Case Report.

A 67-year-old male with a past medical history of coronary artery disease, hypertension, and obesity presented with severe left knee pain and severe tricompartmental osteoarthritis. After failing conservative treatments and completing a preoperative medical workup, the patient was scheduled for total knee arthroplasty. Intraoperatively, a pathologic fracture of the distal femur was discovered, and the procedure was aborted. Histopathologic evaluation of the femur fracture revealed diffuse large B-cell lymphoma. Intraoperative discovery of a pathologic fracture should be treated as an underlying malignancy until proven otherwise. In these cases, surgery should be aborted until definitive diagnosis and management can be planned.

Awareness and Underlying Factors for Total Knee Arthroplasty Reluctance in Saudi Arabia.

Background Total knee arthroplasty (TKA) is a successful surgical intervention for advanced knee arthritis. The efficacy of TKA in reducing pain and restoring joint function has been well documented. Despite the rewarding outcomes of TKA for knee osteoarthritis patients, their willingness to consider the procedure is limited. Aim This study aimed to assess patients' awareness and knowledge of total knee arthroplasty benefits and complications. Further, the reasons and factors contributing to reluctance among orthopedic patients in Saudi Arabia should be determined. Methods An online, structured, and self-administered questionnaire was used to collect data from adult orthopedic patients of both genders who were reluctant to undergo total knee arthroplasty despite surgeons' recommendations. The online questionnaire link was shared across multiple platforms, orthopedic forums, and healthcare social media channels. Qualitative data were presented as frequencies and percentages, while continuous data were reported as the mean (standard deviation [SD]). The statistical package for the social sciences software program was used for statistical analysis. Results A total of 629 participants were involved. The awareness of the expected benefits score, on a scale from 7 to 35, showed a mean (SD) of 20.9 (5.6). The score of the attitude towards expected complications, on a scale from 5 to 25, had a mean (SD) of 15.2 (3.6). The attitude towards the expected complications showed a significantly higher mean (SD) score in the older group aged >60 years than the younger one aged <40 years (15.7 (4.1) vs. 14.9 (3.5), respectively). Likewise, overweight and obese participants showed a significantly higher mean (SD) expected complications score compared to the healthy and underweight ones (15.4 (3.7) vs. 14.8 (3.5), respectively). The recorded reasons for refusal to undergo TKA were fear of anesthesia complications (317, 50.4%), followed by financial limitations (245, 39.0%), the unavailability of experienced surgeons (232, 36.9%), and fear of unfavorable outcomes (189, 30.0%). Conclusion There was a gap in knowledge and awareness of total knee arthroplasty among orthopedic patients in Saudi Arabia. Perceptions of benefits were inadequate, and there were misconceptions about the expected complications. The level of expected complications was higher among elderly and obese patients. Furthermore, fear of anesthesia complications and unfavorable outcomes, in addition to economic and financial problems, constituted major barriers to undergoing the procedure.

Change in lower limb length following total knee arthroplasty.

BACKGROUND: Length variations of the lower limbs after total knee arthroplasty (TKA) constitute a poorly evaluated parameter and can be associated with worse functional outcomes. The objectives of this study were to: 1) describe the variations in the lower limb length after TKA according to the digital accuracy of the computerized navigation system used for prosthesis implantation, 2) describe patient sensation of limb length modification at 3 months postoperatively and to identify its risk factors, 3) identify factors affecting lower limb length modification and to analyze the predictive value causing in the patient the sensation of lower limb discrepancy. HYPOTHESIS: We hypothesize that there may be a lower limb length discrepancy after TKA, which may cause some distress to the patient. PATIENTS AND METHODS: This prospective study included 100 TKAs implanted with navigation gap-balanced adjusted mechanical alignment. Were compared the length of the lower limb before and after implantation and the patient's changes in leg length perception at 3 months postoperatively. A subgroup analysis was performed according to preoperative knee deformities: varus knee was an HKA < 177 °, normal knee was an HKA between 117°-183 ° and valgus was an HKA >183 °. RESULTS: Ninety-seven out of 100 patients experienced lengthening compared to the preoperative ipsilateral length, and twenty-three experienced lengthening greater than 10 mm. The mean lengthening was 7.3 mm (maximum 24.8 mm). Lengthening was significantly greater in valgus knees 9.9 mm [range, 2.0-24.8] than in varus 7.2 mm [range, 1.46-19.4] and normal knees 4.11 mm [range, 0.4-11.4] (p < 0.05). The correction of frontal and sagittal deformation were risk factors for limb length modification (OR = 0.595; 95% CI (0.544-0.816) (p = 0.001), OR = 0.396; 95% CI (0.351-0.653) (p = 0.001)). Twenty-two patients reported a sensation of limb length change: 11 (50%) reported equalization, whereas the remainder reported lengthening with a leg length difference. The preoperative sensation of lower limb length inequality was the unique factor affecting the patient's perception post-surgery (OR = 37.50; 95% CI (9.730-144.526) (p = 0.0001)). A threshold value of 6.6 mm was identified for the sensation of limb length modification. CONCLUSION: Navigation is a tool for describing ipsilateral leg length variations after TKA. These variations are significant and perhaps explain some patient dissatisfaction. A partial correction of the frontal deformity according to the knee phenotype could limit the risk of modification of the native length. LEVEL OF EVIDENCE: IV; Descriptive therapeutic prospective study.

Knee Osteoarthritis associated with Extra-Articular Deformity treated by Total Knee Arthroplasty plus simultaneous Corrective Osteotomy. / "Artrosis de rodilla asociada a deformidad extra-articular tratada mediante prótesis total de rodilla y osteotomía correctora de forma simultánea".

BACKGROUND: Correct mechanical limb alignment is crucial in Total Knee Arthroplasty (TKA) and is particularly difficult to achieve when the knee osteoarthritis (KOA) is associated with an Extra-Articular Deformity (EAD). Our objective is to present a surgical option in cases of severe knee arthritis associated with an EAD (indications, mechanical planning and surgical technique), pros and cons and discuss the results with this one-stage technique. METHODS: We retrospectively reviewed all cases of severe KOA associated with EAD treated surgically in our institution from 2010-2016. In our study, we only included cases treated via simultaneous TKA and corrective osteotomy (CO) and with a minimum follow-up period of three years. In terms of imaging, we determined the apex and angulation of the EAD as well as the modification of the mechanical parameters post-treatment. The pre- and postoperative clinical assessment was performed using the Knee Society Score (KSS). RESULTS: Ten patients (10 knees) underwent combined surgery (simultaneous TKA and CO). The mean age was 67.7 years and the mean follow-up period was 49.2 months. The mechanical parameters were consistently corrected in the post-operative period. The mechanical axis deviation (MAD) shifted from a mean value of 6.9 cm to 0.45 cm and the joint line was rendered horizontal in all cases. In none of the cases did the bone resection affect the insertion of the colateral ligaments. The mean KSS value improved from 32.3 points preoperatively to 79.4 postoperatively. There were no major complications, but there were two planning errors that did not impact upon the end result. CONCLUSIONS: In severe associated KOA and EAD, the combined surgical treatment proposed achieves in one stage an effective anatomical and mechanical correction which is crucial to optimise clinical results and implant durability. The surgery is complex and requires careful planning. LEVEL OF EVIDENCE: Level IV Case series.