Objectives. Osteoarthritis (OA) is the most common form of arthritis, affecting approximately 15% of the human population. Recently, increased concentration of nitric oxide in serum and synovial fluid in patients with OA has been observed. However, the exact role of nitric oxide in the initiation of OA has not been elucidated. The aim of the present study was to investigate the role of nitric oxide in innate immune regulation during OA initiation in rats. Methods. Rat OA was induced by performing meniscectomy surgery while cartilage samples were collected 0, 7, and 14 days after surgery. Cartilage cytokine levels were determined by using enzyme-linked immunosorbent assay, while other proteins were assessed by using Western blot. Results. In the time course of the study, nitric oxide was increased seven and 14 days after OA induction. Pro-inflammatory cytokines including tumour necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 were decreased. L-NG-Nitroarginine methyl ester (L-NAME, a non-specific nitric oxide synthase inhibitor) significantly decreased cartilage nitric oxide and blocked immune suppression. Further, L-NAME decreased Matrix metalloproteinase (MMPs) and increased tissue inhibitor of metalloproteinase (TIMP) expression in meniscectomised rats. Conclusion. Nitric oxide-dependent innate immune suppression protects cartilage from damage in the early stages of OA initiation in rats. Cite this article: C-C. Hsu, C-L. Lin, I-M. Jou, P-H. Wang, J-S. Lee. The protective role of nitric oxide-dependent innate immunosuppression in the early stage of cartilage damage in rats: Role of nitric oxide in ca rtilage da mage. Bone Joint Res 2017;6:253–258. DOI: 10.1302/2046-3758.64.BJJ-2016-0161.R1

Aims

This study uses prospective registry data to compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum.

Aims

Thresholds of acceptable early migration of the components in total knee arthroplasty (TKA) have traditionally ignored the effects of patient and implant factors that may influence migration. The aim of this study was to determine which of these factors are associated with overall longitudinal migration of well-fixed tibial components following TKA.

Aims

The aim of this study was to inform the epidemiology and treatment of slipped capital femoral epiphysis (SCFE).

Aims. Tibiofemoral alignment is important to determine the rate of progression of osteoarthritis and implant survival after total knee arthroplasty (TKA). Normally, surgeons aim for neutral tibiofemoral alignment following TKA, but this has been questioned in recent years. The aim of this study was to evaluate whether varus or valgus alignment indeed leads to increased medial or lateral tibiofemoral forces during static and dynamic weight-bearing activities. Patients and Methods. Tibiofemoral contact forces and moments were measured in nine patients with instrumented knee implants. Medial force ratios were analysed during nine daily activities, including activities with single-limb support (e.g. walking) and double-limb support (e.g. knee bend). Hip-knee-ankle angles in the frontal plane were analysed using full-leg coronal radiographs. . Results. The medial force ratio strongly correlated with the tibiofemoral alignment in the static condition of one-legged stance (R² = 0.88) and dynamic single-limb loading (R² = 0.59) with varus malalignment leading to increased medial force ratios of up to 88%. In contrast, the correlation between leg alignment and magnitude of medial compartment force was much less pronounced. A lateral shift of force occurred during activities with double-limb support and higher knee flexion angles. . Conclusion. The medial force ratio depends on both the tibiofemoral alignment and the nature of the activity involved. It cannot be generalised to a single value. Higher medial ratios during single-limb loading are associated with varus malalignment in TKA. The current trend towards a ‘constitutional varus’ after joint replacement, in terms of overall tibiofemoral alignment, should be considered carefully with respect to the increased medial force ratio. Cite this article: Bone Joint J 2017;99-B:779–87

Aims. To assess the long-term effect of distal trochanteric transfer (DTT) on the clinical and radiographic outcomes of patients with Legg-Calvé-Perthes’ disease (LCPD) following a varus derotational osteotomy (VDRO). Patients and Methods. For this single centre cross-sectional retrospective study we analysed the data of 22 patients (24 hips) with LCPD who had greater trochanteric overgrowth (GTO), following a VDRO performed in our institution between 1959 and 1983. GTO was defined as an articular trochanteric distance (ATD) of < 5 mm. We compared the radiographic and clinical outcomes of patients who underwent DTT for GTO (ten patients, ten hips) with those who did not (12 patients, 14 hips). Age at presentation was 6.9 years (4 to 10) and 8.0 years (3.2 to 12) respectively. Symptoms associated with the hip and general quality of life were assessed using the Harris hip score (HHS) and the Short Form (SF)-36 questionnaires. Results. At long-term follow-up of the DTT group, the ATD was 21.7 mm (standard deviation (. sd. ) 9.8) and the centro-trochanteric distance (CTD) was 13.8 mm (. sd. 8.3). In the control group the ATD was -0.6 mm (. sd. 7.8) and the CTD was 32.5 mm (. sd. 10.2). These differences were statistically significant (p < 0.001). The mean HHS and SF-36 scores were 68.4 (. sd. 25.0) and 62.0 (. sd. 27.7) for the DTT group and 73.2 (. sd. 24.2) and 73.3 (. sd. 21.5) for the control group, respectively. There was no statistically significant difference in the HHS (p = 0.63) or SF-36 score (p = 0.25). There were four patients who had undergone hip arthroplasty in the DTT group (40%) and one patient (7.1%) in the control group (p = 0.07). The mean age at the time of arthroplasty was 45.3 years (42.1 to 56.5) and 43.6 years respectively. Six patients in the DTT group suffered from moderate to severe osteoarthritis (Tönnis grade 2 or 3) compared with eight patients in the control group (60% versus 57.1%, p = 0.61). Conclusion. Although DTT improved the radiographic results in the long-term follow-up of patients with GTO following VDRO, there was no clinical benefit seen in the HHS, SF-36 or incidence of osteoarthritis compared with patients who had not undergone DTT. Cite this article: Bone Joint J 2017;99-B:987–92

Aims. The aim of this study was to identify patient- and surgery-related risk factors for sustaining an early periprosthetic fracture following primary total hip arthroplasty (THA) performed using a double-tapered cementless femoral component (Bi-Metric femoral stem; Biomet Inc., Warsaw, Indiana). Patients and Methods. A total of 1598 consecutive hips, in 1441 patients receiving primary THA between January 2010 and June 2015, were retrospectively identified. Level of pre-operative osteoarthritis, femoral Dorr type and cortical index were recorded. Varus/valgus placement of the stem and canal fill ratio were recorded post-operatively. Periprosthetic fractures were identified and classified according to the Vancouver classification. Regression analysis was performed to identify risk factors for early periprosthetic fracture. Results. The mean follow-up was 713 days (1 to 2058). A total of 48 periprosthetic fractures (3.0%) were identified during the follow-up and median time until fracture was 16 days, (interquartile range 10 to 31.5). Patients with femoral Dorr type C had a 5.2 times increased risk of post-operative periprosthetic fracture compared with type B, while female patients had a near significant two times increased risk over time for post-operative fracture. Conclusion. Dorr type C is an independent risk factor for early periprosthetic fracture, following THA using a double tapered cementless stem such as the Bi-Metric. Surgeons should take bone morphology into consideration when planning for primary THA and consider using cemented femoral components in female patients with poor bone quality. Cite this article: Bone Joint J 2017;99-B:451–7

Recognized anatomic variations that lead to patella instability include patella alta and trochlea dysplasia. Lateralization of the extensor mechanism relative to the trochlea is often considered to be a contributing factor; however, controversy remains as to the degree this contributes to instability and how this should be measured. As the tibial tuberosity-trochlear groove (TT-TG) is one of most common imaging measurements to assess lateralization of the extensor mechanism, it is important to understand its strengths and weaknesses. Care needs to be taken while interpreting the TT-TG value as it is affected by many factors. Medializing tibial tubercle osteotomy is sometimes used to correct the TT-TG, but may not truly address the underlying anatomical problem. This review set out to determine whether the TT-TG distance sufficiently summarizes the pathoanatomy, and if this assists with planning of surgery in patellar instability.

Cite this article: Bone Jt Open 2022;3(3):268–274.

Aims

This study compared the cobalt and chromium serum ion concentration of patients treated with two different metal-on-metal (MoM) hinged total knee arthroplasty (TKA) systems, as well as a titanium nitride (TiN)-coated variant.

In this study, we evaluated patient-reported outcomes, the rate of revision and the indications for revision following resurfacing hemiarthroplasty of the shoulder in patients with osteoarthritis. All patients with osteoarthritis who underwent primary resurfacing hemiarthroplasty and reported to the Danish Shoulder Arthroplasty Registry (DSR), between January 2006 and December 2010 were included. There were 772 patients (837 arthroplasties) in the study. The Western Ontario Osteoarthritis of the Shoulder (WOOS) index was used to evaluate patient-reported outcome 12 months (10 to 14) post-operatively. The rates of revision were calculated from the revisions reported to the DSR up to December 2011 and by checking deaths with the Danish National Register of Persons. A complete questionnaire was returned by 688 patients (82.2%). The mean WOOS was 67 (0 to 100). A total of 63 hemiarthroplasties (7.5%) required revision; the cumulative five-year rate of revision was 9.9%. Patients aged < 55 years had a statistically significant inferior WOOS score, which exceeded the minimal clinically important difference, compared with older patients (mean difference 14.2 (8.8; 95% CI 19.6; p < 0.001), but with no increased risk of revision. There was no significant difference in the mean WOOS or the risk of revision between designs of resurfacing hemiarthroplasty. Cite this article: Bone Joint J 2014;96-B:519–25

Aims. Little is known about employment following total knee arthroplasty (TKA). This study aims to identify factors which predict return to work following TKA in patients of working age in the United Kingdom. Patients & Methods. We prospectively assessed 289 patients (289 TKAs) aged ≤ 65 years who underwent TKA between 2010 and 2013. There were 148 women. The following were recorded pre-operatively: age, gender, body mass index, social deprivation, comorbidities, indication for surgery, work status and nature of employment, activity level as assessed by the University of California, Los Angeles (UCLA) activity score and Oxford Knee Score (OKS). The intention of patients to return to work or to retire was not assessed pre-operatively. At a mean of 3.4 years (2 to 4) post-operatively, the return to work status, OKS, the EuroQol-5 dimensions (EQ-5D) score, UCLA activity score and Work, Osteoarthritis and joint-Replacement (WORQ) score were obtained. Univariate and multivariate analyses were performed. Results. Of 261 patients (90%) who were working before TKA, 105 (40%) returned to any job, including 89 (34%) who returned to the same job at a mean of 13.5 weeks (2 to 104) post-operatively. A total of 108 (41%) retired following TKA and 18 remained on welfare. Patients not working before the operation did not return to work. Median UCLA scores improved in 125 patients (58%) from 4 (mild activity) to 6 (moderate activity) (p < 0.001). Significant (p < 0.05) factors which were predictive of return to any work included age, heavy or moderate manual work, better post-operative UCLA, OKS and EQ-5D general health scores. Significant predictive factors of return to the same work included age, heavy or moderate manual work and post-operative OKS. Multivariate analysis confirmed heavy or moderate manual work and age to independently predict a return to either any or the same work. All patients aged < 50 years who were working pre-operatively returned to any work as did 60% of those aged between 50 and 54 years, 50% of those aged between 55 and 59 years and 24% those aged between 60 and 65 years. . Conclusion. If working pre-operatively, patients aged < 50 years invariably returned to work following TKA, but only half of those aged between 50 to 60 years returned. High post-operative activity levels and patient reported outcome measures do not predict return to work following TKA. Cite this article: Bone Joint J 2017;99-B:1037–46

Aims

There is conflicting evidence on the safety of intra-articular injections of hyaluronic acid (HA) or corticosteroids (CSs) before total knee arthroplasty (TKA). We performed a meta-analysis of the relationship between intra-articular injections and subsequent infection rates after TKA.

Aims. The aim of this study was to compare the post-operative radiographic and clinical outcomes between kinematically and mechanically aligned total knee arthroplasties (TKAs). . Patients and Methods. A total of 60 TKAs (30 kinematically and 30 mechanically aligned) were performed in 60 patients with varus osteoarthritis of the knee using a navigation system. The angles of orientation of the joint line in relation to the floor, the conventional and true mechanical axis (tMA) (the line from the centre of the hip to the lowest point of the calcaneus) were compared, one year post-operatively, on single-leg and double-leg standing long leg radiographs between the groups. The range of movement and 2011 Knee Society Scores were also compared between the groups at that time. Results. The angles of orientation of the joint line in the kinematic group changed from slight varus on double-leg standing to slight valgus with single-leg standing. The mechanical axes in the kinematic group passed through a neutral position of the knee in the true condition when the calcaneus was considered. The post-operative angles of flexion and functional activity scores were significantly better in the kinematic than in the mechanical group (p < 0.003 and 0.03, respectively). Conclusion. A kinematically aligned TKA results in a joint line which has a more parallel orientation in relation to the floor during single- and double-leg standing, and more neutral weight-bearing in tMA than a mechanically aligned TKA. Cite this article: Bone Joint J 2017;99-B:640–6

Objectives. Unicompartmental knee arthroplasty (UKA) is a potential treatment for isolated bone on bone osteoarthritis when limited to a single compartment. The risk for revision of UKA is three times higher than for total knee arthroplasty (TKA). The aim of this review was to discuss the different revision options after UKA failure. Materials and Methods. A search was performed for English language articles published between 2006 and 2016. After reviewing titles and abstracts, 105 papers were selected for further analysis. Of these, 39 papers were deemed to contain clinically relevant data to be included in this review. Results. The most common reasons for failure are liner dislocation, aseptic loosening, disease progression of another compartment and unexplained pain. . UKA can be revised to or with another UKA if the failure mode allows reconstruction of the joint with UKA components. In case of disease progression another UKA can be added, either at the patellofemoral joint or at the remaining tibiofemoral joint. Often the accompanying damage to the knee joint doesn’t allow these two former techniques resulting in a primary TKA. In a third of cases, revision TKA components are necessary. This is usually on the tibial side where augments and stems might be required. Conclusions. In case of failure of UKA, several less invasive revision techniques remain available to obtain primary results. Revision in a late stage of failure or because of surgical mistakes might ask for the use of revision components limiting the clinical outcome for the patients. Cite this article: Bone Joint J 2017;99-B(1 Supple A):65–9

Aims

In the repair of condylar cartilage injury, synovium-derived mesenchymal stem cells (SMSCs) migrate to an injured site and differentiate into cartilage. This study aimed to confirm that histone deacetylase (HDAC) inhibitors, which alleviate arthritis, can improve chondrogenesis inhibited by IL-1β, and to explore its mechanism.

Aims

Golf is a popular pursuit among those requiring total hip arthroplasty (THA). The aim of this study was to determine if participating in golf is associated with greater functional outcomes, satisfaction, or improvement in quality of life (QoL) compared to non-golfers.