Aims. The aim of this study is to compare the effectiveness and safety of thromboprophylactic treatments in patients undergoing primary total knee arthroplasty (TKA). Methods. Using nationwide medical registries, we identified patients with a primary TKA performed in Denmark between 1 January 2013 and 31 December 2018 who received thromboprophylactic treatment. We examined the 90-day risk of venous thromboembolism (VTE), major bleeding, and all-cause mortality following surgery. We used a Cox regression model to compute hazard ratios (HRs) with 95% confidence intervals (CIs) for each outcome, pairwise comparing treatment with dalteparin or dabigatran with rivaroxaban as the reference. The HRs were both computed using a multivariable and a propensity score matched analysis. Results. We identified 27,736 primary TKA patients who received thromboprophylactic treatment (rivaroxaban (n = 18,846); dalteparin (n = 5,767); dabigatran (n = 1,443); tinzaparin (n = 1,372); and enoxaparin (n = 308)). In the adjusted multivariable analysis and compared with rivaroxaban, treatment with dalteparin (HR 0.68 (95% CI 0.49 to 0.92)) or dabigatran (HR 0.31 (95% CI 0.13 to 0.70)) was associated with a decreased risk of VTE. No statistically significant differences were observed for major bleeding or all-cause mortality. The propensity score matched analysis yielded similar results. Conclusion. Treatment with dalteparin or dabigatran was associated with a decreased 90-day risk of VTE following primary TKA surgery compared with treatment with rivaroxaban. Cite this article: Bone Joint J 2021;103-B(10):1571–1577

The administration of heparin during operation has been reported to enhance the efficacy of thromboprophylaxis in patients undergoing total hip replacement. We have performed a small pilot study in which intraoperative doses of heparin were given in addition to the usual postoperative thromboprophylaxis with enoxaparin in 32 patients undergoing total knee replacement. The primary endpoint was deep-vein thrombosis (DVT) as demonstrated by bilateral venography on 6 ± 2 days after operation. Sixteen patients developed DVT; in two the thrombosis was proximal as well as distal and in one the occurrence was bilateral. There was one major haemorrhage. These results are similar to those obtained with the use of postoperative thromboprophylaxis with enoxaparin alone. They do not provide support for the initiation of a larger randomised trial of this approach to management

Aims

In total knee arthroplasty (TKA), blood loss continues internally after surgery is complete. Typically, the total loss over 48 postoperative hours can be around 1,300 ml, with most occurring within the first 24 hours. We hypothesize that the full potential of tranexamic acid (TXA) to decrease TKA blood loss has not yet been harnessed because it is rarely used beyond the intraoperative period, and is usually withheld from ‘high-risk’ patients with a history of thromboembolic, cardiovascular, or cerebrovascular disease, a patient group who would benefit greatly from a reduced blood loss.

Patients who undergo total knee replacement (TKR)are at high risk of venous thromboembolism. Low-molecular-weight heparins (LMWH) are the most suitable chemical prophylactic agents but there are some uncertainties about their safety and effectiveness. The foot pump offers an alternative. We randomised 229 patients undergoing primary, unilateral TKR to receive either the A-V Impulse foot pump or enoxaparin, a LMWH. Ascending venography was undertaken between the sixth and eighth postoperative day in 188 patients without knowledge of the randomisation category. The prevalence of venographic deep-vein thrombosis was 58% (57/99) in the foot-pump group and 54% (48/89) in the LMWH group which was not statistically significant. There were four cases of proximal thrombi and two of fatal pulmonary emboli in the foot-pump group and none in the LMWH group. There were fewer haemorrhagic complications and soft-tissue effects in the foot-pump group. We conclude that the neither method provides superior prophylaxis

Aims

To describe the risk of periprosthetic joint infection (PJI) and reoperation in patients who have an acute, traumatic wound dehiscence following total knee arthroplasty (TKA).

Aims

In the last decade, interest in partial knee arthroplasties and bicruciate retaining total knee arthroplasties has increased. In addition, patient-related outcomes and functional results such as range of movement and ambulation may be more promising with less invasive procedures such as bicompartmental arthroplasty (BCA). The purpose of this study is to evaluate clinical and radiological outcomes after a third-generation patellofemoral arthroplasty (PFA) combined with a medial or lateral unicompartmental knee arthroplasty (UKA) at mid- to long-term follow-up.

Aims

Our aim was to examine the clinical and radiographic outcomes in 257 consecutive Oxford unicompartmental knee arthroplasties (OUKAs) (238 patients), five years post-operatively.

Total knee arthroplasty (TKA) is known to lead to a reduction in periprosthetic bone mineral density (BMD). In theory, this may lead to migration, instability and aseptic loosening of the prosthetic components. Bisphosphonates inhibit bone resorption and may reduce this loss in BMD. We hypothesised that treatment with bisphosphonates and calcium would lead to improved BMD and clinical outcomes compared with treatment with calcium supplementation alone following TKA. A total of 26 patients, (nine male and 17 female, mean age 67 years) were prospectively randomised into two study groups: alendronate and calcium (bisphosphonate group, n = 14) or calcium only (control group, n = 12). Dual energy X-ray absorptiometry (DEXA) measurements were performed post-operatively, and at three months, six months, one, two, four, and seven years post-operatively.

Mean femoral metaphyseal BMD was significantly higher in the bisphosphonate group compared with controls, up to four years following surgery in some areas of the femur (p = 0.045). BMD was observed to increase in the lateral tibial metaphysis in the bisphosphonate group until seven years (p = 0.002), and was significantly higher than that observed in the control group throughout (p = 0.024). There were no significant differences between the groups in the central femoral metaphyseal, tibial medial metaphyseal or diaphyseal regions of interest (ROI) of either the femur or tibia.

Bisphosphonate treatment after TKA may be of benefit for patients with poor bone quality. However, further studies with a larger number of patients are necessary to assess whether this is clinically beneficial.

Cite this article: Bone Joint J 2015;97-B:337–45.

The role of arthroscopy in the treatment of soft-tissue injuries associated with proximal tibial fractures remains debatable. Our hypothesis was that MRI over-diagnoses clinically relevant associated soft-tissue injuries. This prospective study involved 50 consecutive patients who underwent surgical treatment for a split-depression fracture of the lateral tibial condyle (AO/OTA type B3.1). The mean age of patients was 50 years (23 to 86) and 27 (54%) were female. All patients had MRI and arthroscopy. Arthroscopy identified 12 tears of the lateral meniscus, including eight bucket-handle tears that were sutured and four that were resected, as well as six tears of the medial meniscus, of which five were resected. Lateral meniscal injuries were diagnosed on MRI in four of 12 patients, yielding an overall sensitivity of 33% (95% confidence interval (CI) 11 to 65). Specificity was 76% (95% CI 59 to 88), with nine tears diagnosed among 38 menisci that did not contain a tear. MRI identified medial meniscal injuries in four of six patients, yielding an overall sensitivity of 67% (95% CI 24 to 94). Specificity was 66% (95% CI 50 to 79), with 15 tears diagnosed in 44 menisci that did not contain tears.

MRI appears to offer only a marginal benefit as the specificity and sensitivity for diagnosing meniscal injuries are poor in patients with a fracture. There were fewer arthroscopically-confirmed associated lesions than reported previously in MRI studies.

Cite this article: Bone Joint J 2014;96-B:1631–6.

In this study we randomised 140 patients who were due to undergo primary total knee arthroplasty (TKA) to have the procedure performed using either patient-specific cutting guides (PSCG) or conventional instrumentation (CI).

The primary outcome measure was the mechanical axis, as measured at three months on a standing long-leg radiograph by the hip–knee–ankle (HKA) angle. This was undertaken by an independent observer who was blinded to the instrumentation. Secondary outcome measures were component positioning, operating time, Knee Society and Oxford knee scores, blood loss and length of hospital stay.

A total of 126 patients (67 in the CI group and 59 in the PSCG group) had complete clinical and radiological data. There were 88 females and 52 males with a mean age of 69.3 years (47 to 84) and a mean BMI of 28.6 kg/m² (20.2 to 40.8). The mean HKA angle was 178.9° (172.5 to 183.4) in the CI group and 178.2° (172.4 to 183.4) in the PSCG group (p = 0.34). Outliers were identified in 22 of 67 knees (32.8%) in the CI group and 19 of 59 knees (32.2%) in the PSCG group (p = 0.99). There was no significant difference in the clinical results (p = 0.95 and 0.59, respectively). Operating time, blood loss and length of hospital stay were not significantly reduced (p = 0.09, 0.58 and 0.50, respectively) when using PSCG.

The use of PSCG in primary TKA did not reduce the proportion of outliers as measured by post-operative coronal alignment.

Cite this article: Bone Joint J 2015;97-B:56–63.

We prospectively followed 171 patients who underwent bilateral unicompartmental knee replacement (UKR) over a period of two years. Of these, 124 (72.5%) underwent a simultaneous bilateral procedure and 47 (27.5%) underwent a staged procedure. The mean cumulative operating time and length of hospital stay were both shorter in the simultaneous group, by 22.5 minutes (p < 0.001) and three days (p < 0.001), respectively. The mean reduction in haemoglobin level post-operatively was greater by 0.15 g/dl in the simultaneous group (p = 0.023), but this did not translate into a significant increase in the number of patients requiring blood transfusion (p = 1.000). The mean hospital cost was lower by $8892 in the simultaneous group (p < 0.001). There was no significant difference in the rate of complications between the groups, and at two-year follow-up there was no difference in the outcomes between the two groups.

We conclude that simultaneous bilateral UKR can be recommended as an appropriate treatment for patients with bilateral medial compartment osteoarthritis of the knee.

Cite this article: Bone Joint J 2013;95-B:788–92.

Tranexamic acid (TEA), an inhibitor of fibrinolysis, reduces blood loss after routine total knee replacement (TKR). However, controversy persists regarding the dosage and timing of administration of this drug during surgery. We performed a prospective randomised controlled study to examine the optimum blood-saving effect of TEA in minimally invasive TKR.

We randomly assigned 151 patients who underwent unilateral minimally invasive TKR to three groups: 1) a placebo group (50 patients); 2) a one-dose TEA group (52 patients), who received one injection of TEA (10 mg/kg) intra-operatively on deflation of the tourniquet; and 3) a two-dose TEA group (49 patients), who received two injections of TEA (10 mg/kg) given pre-operatively and intra-operatively. Total blood loss was calculated from the maximum loss of haemoglobin. All patients were followed clinically for the presence of venous thromboembolism (VTE).

The mean total blood loss was significantly higher in the placebo group than in the other two groups (1222 ml (845 to 2043) versus 1035 ml (397 to 1934) and 986 ml (542 to 1811), respectively (both p < 0.0001)). The mean blood loss was not significantly different between the one- and two-TEA groups (p = 0.148). The mean transfusion rate was higher in the placebo group than in the other two groups (22% versus 3.8% (p = 0.006) and 6.1% (p = 0.041), respectively) and there was no statistically significant difference in the mean transfusion rate between the one- and two-TEA groups (p = 0.672). Only one patient, in the two-dose group, had a radiologically confirmed deep venous thrombosis.

Our prospective randomised controlled study showed that one intra-operative injection of TEA is effective for blood conservation after minimally invasive TKR.

The purpose of this study was to investigate whether a gender-specific high-flexion posterior-stabilised (PS) total knee replacement (TKR) would offer advantages over a high-flex PS TKR regarding range of movement (ROM), ‘feel’ of the knee, pain and satisfaction, as well as during activity. A total of 24 female patients with bilateral osteoarthritis entered this prospective, blind randomised trial in which they received a high-flex PS TKR in one knee and a gender-specific high-flexion PS TKR in the other knee. At follow-up, patients were assessed clinically measuring ROM, and questioned about pain, satisfaction and daily ‘feel’ of each knee. Patients underwent gait analysis pre-operatively and at one year, which yielded kinematic, kinetic and temporospatial parameters indicative of knee function during gait. At final follow-up we found no statistically significant differences in ROM (p = 0.82). The median pain score was 0 (0 to 8) in both groups (p = 0.95). The median satisfaction score was 9 (4 to 10) in the high-flex group and 8 (0 to 10) in the gender-specific group (p = 0.98). The median ‘feel’ score was 9 (3 to 10) in the high-flex group and 8 (0 to 10) in the gender-specific group (p = 0.66). Gait analysis showed no statistically significant differences between the two prosthetic designs in any kinematic, kinetic or temporospatial parameters.

Both designs produced good clinical results with significant improvements in several gait parameters without evidence of any advantage in the gender-specific design.

This prospective study compares the outcome of 157 hydroxyapatite (HA)-coated tibial components with 164 cemented components in the ROCC Rotating Platform total knee replacement in 291 patients. The mean follow-up was 7.6 years (5.2 to 11). There were two revisions for loosening: one for an HA-coated and one for a cemented tibial component. Radiological evaluation demonstrated no radiolucent lines with the HA-coated femoral components. A total of three HA-coated tibial components exhibited radiolucent lines at three months post-operatively and these disappeared after three further months of protected weight-bearing. With HA-coated components the operating time was shorter (p <  0.006) and the radiological assessment of the tibial interface was more stable (p < 0.01). Using revision for aseptic loosening of the tibial component as the end point, the survival rates at nine years was identical for both groups at 99.1%.

Our results suggest that HA-coated components perform at least as well as the same design with cemented components and compare favourably with those of series describing cemented or porous-coated knee replacements, suggesting that fixation of both components with hydroxyapatite is a reliable option in primary total knee replacement.

Bilateral simultaneous total knee replacement (TKR) has been considered by some to be associated with increased morbidity and mortality. Our study analysed the outcome of 150 consecutive, but selected, bilateral simultaneous TKRs and compared them with that of 271 unilateral TKRs in a standardised fast-track setting. The procedures were performed between 2003 and 2009.

Apart from staying longer in hospital (mean 4.7 days (2 to 16) versus 3.3 days (1 to 25)) and requiring more blood transfusions, the outcome at three months and two years was similar or better in the bilateral simultaneous TKR group in regard to morbidity, mortality, satisfaction, the range of movement, pain, the use of a walking aid and the ability to return to work and to perform activities of daily living. Bilateral simultaneous TKR can therefore be performed as a fast-track procedure with excellent results.