Quality of cementing in hemiarthroplasty for elderly neck of femur fractures does not affect short term functional outcomes.

INTRODUCTION: Cemented hip hemiarthroplasty is a routine surgical option for elderly neck of femur (NOF) fractures. It is uncertain if quality of cementing has any effect on functional outcomes. The aim of this study was to determine if the quality of cementing would affect short term functional outcomes in elderly neck of femur fractures. MATERIALS AND METHODS: Retrospective analysis of 637 single-centre cemented hip hemiarthroplasties from 2014 to 2021 was performed. Each post-operative radiograph was double-read by 2 authors (1 resident and 1 fellowship trained surgeon) to determine quality of cementing via the Barrack grading. Disagreements were reviewed by a third reader. Cement grades were grouped as Optimal (Barrack grade A-B), or Suboptimal (Barrack grade C-D). Functional outcomes were compared using mobility (community- or home-ambulant), assistance required for mobility, and Modified Barthel Index (MBI). Surgical parameters were compared between the groups. RESULTS: There were 429 Optimal and 208 Suboptimal cases of cementing performed. There was no difference in age, American Society of Anesthesiologists score, mobility, assistance required, and MBI score pre-operatively (p > 0.05). Patients in the "Suboptimal" cementing group had a higher Charlson Comorbidity Index (CCI) score (p < 0.001). At 1 year post-operation, there was no significant difference between "Optimal" and "Suboptimal" cementing with regards to the proportion of community ambulators (30.2% vs. 25.7%, p = 0.252), walking independence (independent walkers (19.8% vs.17.3%), independent walkers with aids (41.3%vs.42.1%), walker with caregiver assistance (29.2%vs.33.7%), wheelchair-bound (9.6%vs.6.9%), p = 0.478), and distribution of MBI score (81.1%vs.82.2% achieving MBI > 60, p = 0.767). There was no significant difference in the proportion of patients with postoperative delirium (7.9% vs. 5.8, p = 0.324) or 1-year mortality rates (3.5% vs. 2.9%, p = 0.685). Except for stem design (12.2% tapered vs 20.1% collared; p = 0.011), no other surgical parameters were significantly different. The kappa value for inter-reader agreement was "substantial" at 0.727 (95% CI 0.682-0.772) (p < 0.001). CONCLUSION: Quality of cementing in cemented hip hemiarthroplasty for elderly NOF fractures does not affect the short-term functional outcomes. In low demand patients and patients at risk of BCIS, optimal cementing may not be necessary to achieve similar short-term functional outcomes. Further studies should be conducted to determine the effect of sub-optimal cementing on long-term functional outcomes.

Shorter length of stay and significant cost savings with ambulatory surgery primary unilateral total knee arthroplasty in Asians using enhanced recovery protocols.

Introduction: Enhanced recovery after surgery (ERAS) in total knee arthroplasty (TKA) has reduced the length of stay (LOS) and cost of TKA in the Western population. Asians had been identified to be at higher odds of non-home discharge following TKA due to cultural differences. The efficacy of ERAS in TKA for Asian patients is less known. We aimed to investigate the efficacy of ERAS in reducing the LOS, transition to ambulatory surgery, improving home discharges, and reducing cost in an Asian population following TKA. Methods: Retrospective analysis was performed on 634 TKA patients in 2017 (pre- ERAS) and 584 TKA patients who had undergone ERAS in 2022 in a tertiary hospital. Results: Patients in 2022 (ERAS) were older (69 ± 7 vs. 68 ± 7 years old, p < 0.001) and had a higher proportion of patients with poorer function (p < 0.001). The LOS reduced from 5.4 days (95% CI:5.2-5.6) to 2.9 days (95% CI:2.7-3.2) (p < 0.001) with about 49 % of patients transitioning to ambulatory surgery and having a LOS of 1.4 days (95 %CI:1.3-1.5). The proportion of patients being discharged home in 2022 (78.9 %) was higher compared to 2017 (62.2 %) (p < 0.001). This saved the hospital 1817.4 inpatient ward bed days, which translated to S$2,124,540.60 of cost saving in a year, and up to S$2397.28 for the individual patient. Conclusion: ERAS after TKA was able to safely achieve LOS comparable to the western population and allowed transition to ambulatory knee replacement in the Asian population. Consequently, this led to higher proportion of home discharges and achieved significant cost saving and hospital bed days.

Intertrochanteric fracture with distal extension: When is the short proximal femoral nail antirotation too short?

INTRODUCTION: The lesser trochanter (LT) fragment in the multifragmentary intertrochanteric femur fracture (AO 31A2.2) may extend distally. If the fragment extends too distally, fixation with a short proximal femoral nail antirotation (PFNA-II) device may not be sufficient. The exact length of distal extension that can be tolerated by the short PFNA-II is not known, therefore it is our objective to determine it. MATERIALS AND METHODS: A finite element analysis was performed on AO 31A2.2 fracture fixed with a 200mm length size 10 PFNA-II. The construct was loaded vertically to clinical failure of 10mm displacement. This was repeated with the size of the LT fragment increasing distally at intervals, up to 120mm from the base of the LT. The process was also repeated with the bone properties substituted with osteoporotic properties. The stiffness, maximum vertical reaction force, and the plastic deformation area were investigated. RESULTS: In both non-osteoporotic and osteoporotic model, the stiffness and the maximum vertical reaction force of the construct dropped significantly when the LT fragment is larger than 40mm. Beyond 40mm of LT fragment size, there was a rapid increase in the area of plastic deformation of the cortical bone distal to the intertrochanteric fracture, signifying structural failure of the construct. CONCLUSION: A long PFNA-II should be considered when fixing a multifragmentary intertrochanteric fracture if the LT fragment extends 40mm distal to the distal base of the LT as the construct fails rapidly upon uniaxial load to failure. Clinically, this threshold may be smaller to account for the multi-axial and dynamic stresses.

Total Knee Arthroplasty in Ochronosis Arthropathy: A Case Report and Systematic Review.

INTRODUCTION: Ochronosis arthropathy (OcA) is a rare condition which may be treated with total knee arthroplasty (TKA) at the end stage. The condition is often discovered only intraoperatively and the ideal choice of TKA is unknown. CASE PRESENTATION: A 54-year-old male with worsening chronic bilateral mechanical knee pain had failed conservative therapy. Posterior stabilised (PS), cemented TKA and patella resurfacing was performed. Intraoperatively, collagenous structures such as the menisci and cartilage were noted to be black. Histological examination showed deposition of large amorphous brown material suggestive of ochronosis. He recovered well and underwent TKA of the contralateral knee the following year. At 2 years postindex TKA, his outcome scores improved and he was satisfied. DISCUSSION AND CONCLUSION: With increasing TKA performed worldwide, a surgeon may eventually be surprised by the above findings once in their lifetime. However, OcA may be considered a likely diagnosis and it is safe to proceed with TKA. There is no particular TKA design that proved to be superior in our systematic review of 19 publications regarding TKA as all reported good outcomes. However, as the pathogenesis of OcA appears to be inflammatory in nature, we suggest using cemented PS TKA with resurfacing of the patella.

Achieving Minimum Clinically Important Difference in Oxford Knee Score and Short Form-36 Physical Component Summary Is Less Likely with Single-Radius Compared with Multiradius Total Knee Arthroplasty in Asians.

Single-radius (SR) and multiradius (MR) total knee arthroplasties (TKAs) have produced similar outcomes, albeit most studies originate from Western nations. There are known knee kinematic differences between Western and Asian patients after TKA. The aim of this study is to compare the short-term patient-reported outcome measures (PROMs) of SR-TKA versus MR-TKA in Asians. Registry data of 133 SR-TKA versus 363 MR-TKA by a single surgeon were analyzed. Preoperative and 2-year postoperative range of motion (ROM) and PROMs were compared with Student's t-test and Mann-Whitney U-test. Logistic regression model was used to evaluate the odds of SR-TKA or MR-TKA achieving the minimum clinically important difference (MCID) of studied outcomes. Patients in both groups had similar age (65.7 ± 7.6 vs. 65.8 ± 8.2 years; p = 0.317), gender proportion (71% females vs. 79% females; p = 0.119), and ethnic distribution (80% Chinese vs. 84% Chinese; p = 0.258). Preoperatively, there were no statistically significant differences between both groups for ROM, Knee Society Score (KSS), Oxford Knee Score (OKS), and Short Form (SF)-36 scores. At 2 years, all outcomes were statistically similar or failed to achieve a difference of MCID. Controlling for all preoperative variables, SR-TKA has significantly lower odds of achieving MCID for OKS (odds ratio [OR]: 0.275, 95% confidence interval [CI]: 0.114-0.663; p = 0.004) and SF-36 Physical Component Summary (PCS) (OR: 0.547; 95% CI: 0.316-0.946; p = 0.031) compared with MR-TKA. In conclusion, there are no significant differences in the absolute PROMs between SR-TKA and MR-TKA at 2 years following TKA in Asians. However, SR-TKA has significantly lower odds of achieving the MCID for OKS and SF-36 PCS.

Developmental dysplasia of the hip: why are we still operating on them? A plea for institutional newborn clinical screening.

INTRODUCTION: Developmental dysplasia of the hip (DDH) is a common orthopaedic condition at birth. Non-surgical management with the Pavlik harness can effectively treat DDH in the newborn by providing an early clinical diagnosis, but open surgeries continue to be performed. We aimed to elucidate the reasons for this. METHODS: A retrospective review was performed of all open surgeries related to DDH from 2006 to 2016. Patients were either born at our institution (Group 1) or outside of it (Group 2). All Group 1 newborns were routinely screened for DDH at birth. RESULTS: 27 patients (Group 1: n = 5, Group 2: n = 22) presented at age 25 ± 19 months. Left-sided DDH (n = 21, 77.8%) and female infants (n = 22, 81.5%) were more common. The mean age at surgery was 40 ± 31 months. The most commonly performed procedure was soft tissue release open reduction with acetabuloplasty (n = 20, 74.1%). Gender, site, median age at presentation and at surgery, and prevalence of risk factors were similar for both groups. Both groups were mostly made up of late presenters (> 3 months; p = 0.34). A few patients had undergone prior treatment (p = 0.64). Newborn screening was the only significantly different variable between the groups (p < 0.01). CONCLUSION: Lack of institutionalised newborn clinical screening appears to be the root cause of late presentation of DDH leading to open surgery for its management. We recommend quality institutionalised newborn clinical screening to reduce the number of late presentations.

Prophylactic fixation or surveillance: predicting subsequent displacement of lateral condyle of humeral fractures based on soft tissue swelling.

BACKGROUND: Nondisplaced or minimally displaced fractures (≤2 mm) of the lateral condyle of the humerus (LCH) could undergo subsequent displacement (>2 mm), which would be a potential surgical indication. We describe a new method to quantify soft tissue swelling in LCH fractures and to identify a threshold value to predict subsequent displacement of LCH fractures. We hypothesized that the larger the soft tissue swelling, the more likely a subsequent displacement would occur. METHODS: Elbow x-ray images (anteroposterior view) at initial presentation in 87 patients with subsequent displacement and in 87 patients with no subsequent displacement were compared. All fractures were initially nondisplaced or minimally displaced. The lateral elbow swelling-to-humeral shaft diameter (LES-H) ratio was measured. A threshold value for diagnosing a subsequent displacement was identified from the receiver operating characteristic curve analysis. RESULTS: Both groups had similar age (subsequent displacement: 5.1 ± 2.3 years vs. no subsequent displacement: 5.7 ± 3.2 years; P = .459). The LES-H ratio was significantly larger in the subsequent displacement group (1.8 ± 0.4 vs. 1.4 ± 0.4, P < .001). The area under the receiver operating characteristic curve was 0.728, which was moderately accurate in predicting subsequent displacement. A threshold LES-H ratio of 1.90 had a sensitivity of 41.4% and specificity of 90.8% in diagnosing subsequent displacement. The odds ratio of having subsequent displacement with LES-H ratio of ≥1.90 was 6.1 (95% confidence interval, 2.7-13.8; P < .001). CONCLUSION: The LES-H ratio could be used to objectively quantify soft tissue swelling in LCH fractures. An LES-H ratio of ≥1.90 was used as threshold value to predict subsequent displacement.

The minimal clinically important difference for Knee Society Clinical Rating System after total knee arthroplasty for primary osteoarthritis.

PURPOSE: The Knee Society Clinical Rating System (KS) is one of the most popular tools used to assess patient outcome after total knee arthroplasty (TKA), but its minimal clinically important difference (MCID) has not been identified. This study aims to identify the MCID of KS function score (KS-FS) and knee score (KS-KS) after TKA in patients with primary knee osteoarthritis. METHODS: The authors retrospectively analysed patients who underwent TKA for primary knee osteoarthritis between 2005 and 2015 in a single institution. KS-FS, KS-KS, and Oxford Knee Score (OKS) were collected pre-operatively and 2 years post-operatively. Patient satisfaction with TKA at 2 years was also collected. Anchor-based approach with 2 external indicators was used. The MCID for KS-FS and KS-KS was determined using simple linear regression according to patient satisfaction with TKA and the MCID of OKS. RESULTS: The mean age of the 550 subjects studied was 66 ± 8 years. There were 373 (67.8 %) female subjects. The KS-FS improved by 22.8 (95 % CI 20.9-24.6) points, and the KS-KS improved by 44.4 (95 % CI 42.6-46.3) points. The MCID identified for KS-FS is between 6.1 (95 % CI 5.1-7.1) and 6.4 (95 % CI 4.4-8.4) and between 5.3 (95 % CI 4.3-6.3) and 5.9 (95 % CI 3.9-7.8) for KS-KS. CONCLUSIONS: This is the first study, to the knowledge of the authors, to identify the MCID of KS. This will allow future trials to have an accurate prediction of sample size. Clinically, physicians will be able to better interpret outcomes of TKA studies to guide a treatment option. LEVEL OF EVIDENCE: IV.

Identifying an Ideal Time Frame for Staged Bilateral Total Knee Arthroplasty to Maximize Functional Outcome.

Compared with staged bilateral total knee arthroplasty (TKA), simultaneous bilateral TKA carries a higher risk of cardiac complications, pulmonary complications, and mortality, especially in patients with preexisting cardiopulmonary disease or advanced age. However, the period of time between staged TKAs that would eliminate these increased risks has yet to be determined. The purpose of this study is to evaluate complication rates and functional outcome in patients who underwent staged bilateral TKA and to determine an optimal time frame for the second knee. The authors retrospectively reviewed 306 patients who underwent staged bilateral TKA between 2002 and 2013. Patients were grouped into 31 to 90, 91 to 180, 181 to 270, and 271 to 365 days interval, where complication and 90-day readmission rates for the second TKA were identified. Patients were also assessed preoperatively and 2 years postoperatively using the Oxford knee score (OKS) and Short-Form (SF)-36. There was no significant difference in complication and 90-day readmission rates between the various groups. The functional outcome of the knees scored 2 years postoperatively using OKS and SF-36 showed comparable results across all four groups. Thus, the authors could not identify an ideal time frame for performing the second TKA with the objective of maximizing functional outcome.

Drain use in total knee arthroplasty is neither associated with a greater transfusion rate nor a longer hospital stay.

PURPOSE: In recent years, the exclusion of a drain in total knee arthroplasty (TKA) is gaining popularity. This retrospective study aims to investigate a tertiary hospital's experience with the use of a drain in TKA. The authors hypothesise that the use of a drain will: (1) increase the peri-operative total blood loss (TBL) and transfusion rate; (2) increase the length of hospital stay (LOS); (3) reduce the 30-day readmission rate and incidence of additional surgical procedure performed. METHODS: Patients who underwent a unilateral primary TKA in 2012 were included. Seven surgeons performed 575 TKAs with the use of drains, while nine other surgeons performed 902 TKAs without the use of drains. The patients were prospectively followed-up for two years. Peri-operative TBL was calculated using the haemoglobin balance method. All patients followed the hospital's transfusion and post-operative rehabilitation protocol. RESULTS: There was a bigger drop in haemoglobin level by 0.5 g/dl (95 % CI, 0.4, 0.6) and greater TBL by 169 ml (95 % CI, 126, 181) in the drain group (both p < 0.001). However, the transfusion rate was 37/575 (6.4 %) and 48/902 (5.3 %) in the drain and no drain groups respectively (p = 0.370), while the LOS was four (IQR, 4, 5) and four (IQR 3, 5) days respectively (p = 0.228). The 30-day readmission rate was 10/575 (1.7 %) in the drain group, compared with 26/902 (2.9 %) in the no-drain group (p = 0.165). The incidence of additional surgical procedure performed was 5/575 (0.9 %) in the drain group, compared with 15/902 (1.7 %) in the no-drain group (p = 0.198). CONCLUSIONS: Although the use of a drain in TKA is associated with greater peri-operative TBL, this additional amount of blood loss does not translate into an increased transfusion rate or a longer LOS. It also does not reduce the 30-day readmission rate and incidence of additional surgical procedure performed on the same knee.

Severe Bilateral Fixed Flexion Deformity-Simultaneous or Staged Total Knee Arthroplasty?

Outcomes of 29 simultaneous (SimBTKA) and 38 staged bilateral total knee arthroplasty (StaBTKA) subjects with severe (≥16°) bilateral fixed flexion deformity (FFD) were retrospectively investigated. SimBTKA patients were significantly younger (63 ± 8 vs 68 ± 7, P > .01). At 2 years, SimBTKA subjects had significantly better residual FFD (2.5° ± 5.1° vs 5.4° ± 6.6°, P = .02) and Knee Society function score (75.7 ± 25.7 vs 69.3 ± 24.1, P = .02). However, Knee Society knee scores, Oxford Knee Scores, and Short Form-36 scores were similar. These suggest no large clinical advantage of SimBTKA over StaBTKA. We feel that severe bilateral FFD is not an absolute indication for SimBTKA.

Three-dimensional development of tensile pre-strained annulus fibrosus cells for tissue regeneration: an in-vitro study.

Prior research has investigated the immediate response after application of tensile strain on annulus fibrosus (AF) cells for the past decade. Although mechanical strain can produce either catabolic or anabolic consequences to the cell monolayer, little is known on how to translate these findings into further tissue engineering applications. Till to date, the application and effect of tensile pre-strained cells to construct a three-dimensional (3D) AF tissue remains unknown. This study aims to investigate the effect of tensile pre-strained exposure of 1 to 24h on the development of AF pellet culture for 3 weeks. Equibiaxial cyclic tensile strain was applied on AF monolayer cells over a period of 24h, which was subsequently developed into a cell pellet. Investigation on cellular proliferation, phenotypic gene expression, and histological changes revealed that tensile pre-strain for 24h had significant and lasting effect on the AF tissue development, with enhanced cell proliferation, and up-regulation of collagen type I, II, and aggrecan expression. Our results demonstrated the regenerative ability of AF cell pellets subjected to 24h tensile pre-straining. Knowledge on the effects of tensile pre-strain exposure is necessary to optimize AF development for tissue reconstruction. Moreover, the tensile pre-strained cells may further be utilized in either cell therapy to treat mild disc degeneration disease, or the development of a disc construct for total disc replacement.

Thermoregulatory and cardiovascular responses to creatine, glycerol and alpha lipoic acid in trained cyclists.

BACKGROUND: It has been shown that supplementation with creatine (Cr) and glycerol (Gly), when combined with glucose (Glu) necessary for the enhancement of Cr uptake by skeletal muscle, induces significant improvements in thermoregulatory and cardiovascular responses during exercise in the heat. PURPOSE: To determine whether Cr/Gly-induced thermoregulatory and cardiovascular responses are maintained when the majority (~75%) of the Glu in the Cr/Gly supplement is replaced with the insulintropic agent alpha lipoic acid (Ala). METHODS: 22 healthy endurance trained cyclists were randomly assigned to receive either 20 g/day (4 × 5 g/day) of Cr, 2 g .kg-1 BM per day (4 × 0.5 g .kg-1 BM per day) of Gly and 150 g/day (4 × 37.5 g/day) of Glu or 20 g/day (4 × 5 g/day) of Cr monohydrate, 2 g .kg-1 BM per day (4 × 0.5 g .kg-1 BM per day) of Gly (100 g/day (4 × 25 g/day) of Glu and 1000 mg/day (4 × 250 mg/day) of Ala for 7 days for 7 days. Exercise trials were conducted pre- and post-supplementation and involved 40 min of constant-load cycling exercise at 70% O2 max by a self-paced 16.1 km time trial at 30°C and 70% relative humidity. RESULTS: Median and range values of TBW increased significantly by 2.1 (1.3-3.3) L and 1.8 (0.2-4.6) L in Cr/Gly/Glu and Cr/Gly/Glu/Ala groups respectively (P = 0.03) and of BM not significantly by 1.8 (0.2-3.0) kg and 1.2 (0.5-2.1) kg in Cr/Gly/Glu and in Cr/Gly/Glu/Ala, respectively (P = 0.75). During constant load exercise, heart rate (HR) and core temperature (Tcore) were significantly lower post-supplementation: HR was reduced on average by 3.3 ± 2.1 beats/min and by 4.8 ± 3.3 beats/min (mean ± SD) and Tcore by 0.2 ± 0.1 (mean ± SD) in the Cr/Gly/Glu and Cr/Gly/Glu/Ala, respectively The reduction in HR and Tcore was not significantly different between the supplementation groups. CONCLUSIONS: In comparison to the established hyper hydrating Cr/Gly/Glu supplement, supplement containing Cr/Gly/Ala and decreased amount of Glu provides equal improvements in thermoregulatory and cardiovascular responses during exercise in the heat.