Purpose. Whether the presence of knee effusion in individuals with knee osteoarthritis (OA) affects periarticular neuromuscular control during gait and thus the joint loading environment is unknown. The purpose was to test the hypothesis that knee effusion presence alters periarticular neuromuscular patterns during gait in individuals with moderate knee OA. Method. 40 patients with medial compartment knee OA participated after giving informed consent. Patients were assessed for the presence of effusion using a brush test and were assigned to the knee effusion (n=20) and no knee effusion (n=20) groups. Surface electrodes were placed in a bipolar configuration over the lateral and medial gastrocnemius, vastus lateralis and medialis, rectus femoris and the lateral and medial hamstrings of the affected limb. Five trials of self-selected walking were completed. Electromyograms (EMG) were collected using an AMT-8 EMG system (Bortec Inc.). An Optotrak motion capture system (Northern Digital Inc.) recorded leg motion. Euler rotations were used to derive knee angles. EMG waveforms were low-pass filtered and amplitude normalized to maximal effort voluntary isometric contractions. Quadriceps, gastrocnemius and hamstring strength was measured from torques produced against a Cybex dynamometer. Principal Component Analysis extracted the predominant waveform features and weighting scores were calculated for each measured waveform. Analysis of variance models test for main effects (group, muscle) and interactions (alpha = 0.05). Bonferonni post hoc testing was employed. Results. No differences in age, body mass index, knee pain, Western Ontario McMaster Osteoarthritis Index scores, gait velocity and muscle strength were found between groups (p>0.05). Gastrocnemius activation was not influenced by the presence of effusion (p>0.05). For individuals with effusion, a greater overall quadriceps activation was found and a prolonged hamstring activation into mid-stance only (p<0.05). Range of motion excursion from heel strike to peak extension during terminal stance was greater with effusion (p<0.05). Conclusion. The hypothesis that knee effusion in those with moderate knee OA is associated with alterations in quadricep and hamstring muscle activation patterns and sagittal plane knee motion during gait was supported. Quadriceps muscle inhibition during the normalization exercises may provide a partial explanation, consistent with results from acute effusion models. However, the hamstring alteration during mid-stance only, no strength differences between the two groups and altered kinematics support that mechanisms other than muscle inhibition are responsible for the altered patterns. These novel findings are a first step at understanding the effects of knee effusion on periarticular muscle function during gait that subsequently can affect the mechanical environment of the joint in those with a more chronic effusion

We prospectively randomised 78 patients into two groups, ‘drains’ or ‘no drains’ to assess the effectiveness of suction drains in reducing haematoma and effusion in the joint and its effect on wound healing after total knee replacement. Ultrasound was used to measure the formation of haematoma and effusion on the fourth post-operative day. This was a semi-quantitative assessment of volume estimation. There was no difference in the mean effusion between the groups (5.91 mm in the drain group versus 6.08 mm in the no-drain, p = 0.82). The mean amount of haematoma in the no-drain group was greater (11.07 mm versus 8.41 mm, p = 0.03). However, this was not clinically significant judged by the lack of difference in the mean reduction in the post-operative haemoglobin between the groups (drain group 3.4 g/dl; no-drain group 3.0 g/dl, p = 0.38). There were no cases of wound infection or problems with wound healing at six weeks in any patient. Our findings indicate that drains do not reduce joint effusion but do reduce haematoma formation. They have no effect on wound healing

1. Details are given of sixty-three consecutive cases with a history of pleural effusion seen at an orthopaedic hospital. 2. Twenty-four of these were post-primary effusions occurring before the onset of symptoms of the orthopaedic lesion. The bone and joint lesions ultimately developing in this group of patients were widely scattered throughout the skeleton. 3. Three others were secondary to adult-type pulmonary lesions. 4. Thirty-six patients had a pleural effusion after the beginning of their orthopaedic tuberculous history. Seven were certainly secondary to operative intervention, six in the thorax near the parietal pleura (costotransversectomy or antero-lateral decompression of the cord) and one from a haematogenous dissemination after fusion of a hip joint. 5. The remainder of this group with pleural effusion during the history of their orthopaedic tuberculous disease numbered twenty-nine. Of these, twenty-five suffered from disease of the thoracic spine; in two more details are defective. Only two definitely had neither pulmonary nor thoracic spinal disease; their lesions were in the lumbar spine. The conclusion is drawn that the overwhelmingly common cause of pleural effusion in patients with orthopaedic tuberculosis who have normal lungs and have not recently suffered spinal decompression is transpleural infection from thoracic spinal disease and that the sequence is by no means rare. It had occurred in approximately one in six of 145 patients with thoracic Pott's disease seen during this investigation. 6. Details are given of a group of cases with thoracic paravertebral abscess tracking laterally. When the abscess is well clear of the spine and spinal ligaments it may project forwards and radiologically it may appear in the antero-posterior chest film as a shadow in the middle of one or other lung field rather than as a shadow obviously connected with the central paravertebral abscess. Aspiration will yield pus from this posterior extra-pleural abscess extension. 7. The belief that Pott's disease most commonly follows direct spread from caseous paraaortic glands secondary to tuberculous pleurisy is discussed. It is concluded that the evidence is insufficient for so sweeping a statement

In order to investigate the difficulty of quadriceps training in the presence of an effusion into the knee we examined 13 patients with chronic effusions by recording isometric muscle strength. Maximal strength was markedly lower in the presence of an effusion, and aspiration of the effusion produced a 13.6% increase in strength (p less than 0.01). A further, small increase of 8% was recorded after intra-articular lignocaine injection. Isometric strength and surface integrated EMG correlated well in six patients. Two reflex mechanisms seem to inhibit quadriceps innervation in the presence of a persistent knee effusion, one mediated by pressure sensitive receptors, the other still unknown. Joint aspiration and systemic or intra-articular anti-inflammatory drug treatments are advised before any programme of quadriceps training to allow maximum effects to be achieved

Aims. The aim of this study was to determine whether closed suction drain (CSD) use influences recovery of quadriceps strength and to examine the effects of drain use on secondary outcomes: quadriceps activation, intra-articular effusion, bioelectrical measure of swelling, range of movement (ROM), pain, and wound healing complications. Patients and Methods. A total of 29 patients undergoing simultaneous bilateral total knee arthroplasty (TKA) were enrolled in a prospective, randomized blinded study. Patients were randomized to receive a CSD in one limb while the contralateral limb had the use of a subcutaneous drain (SCDRN) without the use of suction (‘sham drain’). Isometric quadriceps strength was collected as the primary outcome. Secondary outcomes consisted of quadriceps activation, intra-articular effusion measured via ultrasound, lower limb swelling measured with bioelectrical impendence and limb girth, knee ROM, and pain. Outcomes were assessed preoperatively and postoperatively at day two, two and six weeks, and three months. Differences between limbs were determined using paired Student’s t-tests or Wilcoxon’s signed-rank tests. Results. No significant differences were identified between limbs prior to surgery for the primary or secondary outcomes. No significant differences in quadriceps strength were seen between CSD and SCDRN limbs at postoperative day two (p = 0.09), two weeks (primary endpoint) (p = 0.7), six weeks (p = 0.3), or three months (p = 0.5). The secondary outcome of knee extension ROM was significantly greater in the CSD limb compared with the SCDRN (p = 0.01) at two weeks following surgery, but this difference was absent at all other intervals. Secondary outcomes of quadriceps activation, intra-articular effusion, lower limb swelling, and pain were not found to differ significantly at any timepoint following surgery. Conclusion. The use of CSD during TKA did not influence quadriceps strength, quadriceps activation, intra-articular effusion, lower limb swelling, ROM, or pain. These results have limited drain use by the authors in primary uncomplicated TKA. Cite this article: Bone Joint J 2019;101-B (7 Supple C):84–90

Introduction: Data on intralesional concentrations of modern anti-tuberculosis drugs isoniazid (H), rifampin (R) and pyrazinamid (Z) in tuberculous pleural effusions and psoas abscesses are scarce. Insight into drug penetration is important since subtherapeutic drug concentrations may result in the selection of a resistant bacterial population and lead to treatment failure. Material and Methods: Intralesional concentrations were measured 2 hours after drug administration in 6 patients with pleural effusions, and 10 with psoas abscesses. Results: Concentrations were variable. The same range was found for pleural effusions and psoas abscesses. Concentrations were below MIC values in none of 15 patients for H, in 2 of 13 for R, and in 8 of 9 for Z. Cmax:MIC ratio was always > 4 for H, in 4 of 13 for R, and in none of 9 for Z. In 5:8 patients receiving all 3 drugs both R and Z had Cmax:MIC ratios < 4, indicating subtherapeutic drug levels. Conclusion: Intralesional drug concentrations of isoniazid (H), rifampin (R), and pyrazinamid (Z) were variable. The same range was found for pleural effusions and psoas abscesses. Cmax:MIC ratio for H was always sufficient, for R in most cases below the desired ratio, and for Z on average 10 times too low. In 5 of 8 patients receiving all 3 drugs, both R and Z had Cmax:MIC ratios below 4, indicating intralesional subtherapeutic drug levels for R and Z. This local monotherapy with H may result in the selection of a resistant bacterial population and lead to failure of treatment. Drainage as additional therapy seems indicated

Aim. Adverse tissue reactions have been a concern in relation to metal components, particularly in hip replacements. We look at a possible correlation between hip joint effusion and metal ion levels. Materials and methods. 56 patients,(42M, 14F) agreed to the study. All had metal-on-mental arthroplasties. Average age was 64.2 (SD 9.8). All patients were asymptomatic. Ultrasound examination performed by one ultrasonographer, using a Sonosite M-Turbo machine with a C60X/5-2 MHz transducer. Cobalt levels were assessed using an inductively coupled plasma mass spectrometer. Chromium levels were assessed using a graphite furnace atomic absorption spectrometer. Results. Average blood ion levels were:. Cobalt 39.02 nmol/L. (SD41.18) range 3 to 215. Chromium 52.51 nmol/L (SD47.48) range 5 to 284. Average Volume: 10.38ml (SD21.3) Range 0 to 219. Conclusion. There was no statistically significant correlation between joint effusion and metal ion levels

Aims. Intra-articular (IA) tumours around the knee are treated with extra-articular (EA) resection, which is associated with poor functional outcomes. We aim to evaluate the accuracy of MRI in predicting IA involvement around the knee. Methods. We identified 63 cases of high-grade sarcomas in or around the distal femur that underwent an EA resection from a prospectively maintained database (January 1996 to April 2020). Suspicion of IA disease was noted in 52 cases, six had IA pathological fracture, two had an effusion, two had prior surgical intervention (curettage/IA intervention), and one had an osseous metastasis in the proximal tibia. To ascertain validity, two musculoskeletal radiologists (R1, R2) reviewed the preoperative imaging (MRI) of 63 consecutive cases on two occasions six weeks apart. The radiological criteria for IA disease comprised evidence of tumour extension within the suprapatellar pouch, intercondylar notch, extension along medial/lateral retinaculum, and presence of IA fracture. The radiological predictions were then confirmed with the final histopathology of the resected specimens. Results. The resection histology revealed 23 cases (36.5%) showing IA disease involvement compared with 40 cases without (62%). The intraobserver variability of R1 was 0.85 (p < 0.001) compared to R2 with κ = 0.21 (p = 0.007). The interobserver variability was κ = 0.264 (p = 0.003). Knee effusion was found to be the most sensitive indicator of IA involvement, with a sensitivity of 91.3% but specificity of only 35%. However, when combined with a pathological fracture, this rose to 97.5% and 100% when disease was visible in Hoffa’s fat pad. Conclusion. MRI imaging can sometimes overestimate IA joint involvement and needs to be correlated with clinical signs. In the light of our findings, we would recommend EA resections when imaging shows effusion combined with either disease in Hoffa’s fat pad or retinaculum, or pathological fractures. Cite this article: Bone Joint J 2023;105-B(6):696–701

Aims. Treatment of high-grade limb bone sarcoma that invades a joint requires en bloc extra-articular excision. MRI can demonstrate joint invasion but is frequently inconclusive, and its predictive value is unknown. We evaluated the diagnostic accuracy of direct and indirect radiological signs of intra-articular tumour extension and the performance characteristics of MRI findings of intra-articular tumour extension. Methods. We performed a retrospective case-control study of patients who underwent extra-articular excision for sarcoma of the knee, hip, or shoulder from 1 June 2000 to 1 November 2020. Radiologists blinded to the pathology results evaluated preoperative MRI for three direct signs of joint invasion (capsular disruption, cortical breach, cartilage invasion) and indirect signs (e.g. joint effusion, synovial thickening). The discriminatory ability of MRI to detect intra-articular tumour extension was determined by receiver operating characteristic analysis. Results. Overall, 49 patients underwent extra-articular excision. The area under the curve (AUC) ranged from 0.65 to 0.76 for direct signs of joint invasion, and was 0.83 for all three combined. In all, 26 patients had only one to two direct signs of invasion, representing an equivocal result. In these patients, the AUC was 0.63 for joint effusion and 0.85 for synovial thickening. When direct signs and synovial thickening were combined, the AUC was 0.89. Conclusion. MRI provides excellent discrimination for determining intra-articular tumour extension when multiple direct signs of invasion are present. When MRI results are equivocal, assessment of synovial thickening increases MRI’s discriminatory ability to predict intra-articular joint extension. These results should be interpreted in the context of the study’s limitations. The inclusion of only extra-articular excisions enriched the sample for true positive cases. Direct signs likely varied with tumour histology and location. A larger, prospective study of periarticular bone sarcomas with spatial correlation of histological and radiological findings is needed to validate these results before their adoption in clinical practice. Cite this article: Bone Jt Open 2024;5(10):944–952

Abstract. Background. Around 5–15% of patients will experience chronic postoperative pain after total knee replacement (TKR) surgery but the source of the pain is unknown. The aim of this study was to assesses patients six months after TKR using magnetic resonance imaging (MRI) of the knee, pain sensory profiles and assessments of pain catastrophizing thoughts. Methods. Forty-six patients had complete postoperative data and were included. MRI findings were scored according to the MRI Osteoarthritis Knee Score (MOAKS) recommendation for Hoffa synovitis, effusion size and bone marrow lesions. Pain sensory profiles included the assessment of pressure pain thresholds (PPTs), temporal summation of pain (TSP) and conditioned pain modulation (CPM). Pain catastrophizing was assessed using the pain catastrophizing scale (PCS). Clinical pain was evaluated using a visual analog scale (VAS, 0–10cm) and groups of moderate-to-severe (VAS>3) and non-to-mild postoperative pain (VAS≤3) were identified. Results. Patients with moderate-to-severe postoperative pain demonstrated higher grades of Hoffa synovitis (P<0.001) and effusion size (P<0.001), lower PPTs (P=0.039), higher TSP (P=0.001) and lower CPM (P=0.014) when compared to patients with non-to-mild postoperative pain. No differences were found in PCS scores. Linear regression models found TSP (P=0.013), PCS (P<0.001), Hoffa synovitis (P=0.036) and effusion size (P=0.003) as independent parameters contributing to the postoperative pain severity. Conclusion. These finding indicate that chronic postoperative after TKR is a combination of joint-related synovitis and effusion in combination with sensitization of central pain mechanisms and pain catastrophizing thoughts

Aims. Pain is the most frequent complaint associated with osteonecrosis of the femoral head (ONFH), but the factors contributing to such pain are poorly understood. This study explored diverse demographic, clinical, radiological, psychological, and neurophysiological factors for their potential contribution to pain in patients with ONFH. Methods. This cross-sectional study was carried out according to the “STrengthening the Reporting of OBservational studies in Epidemiology” statement. Data on 19 variables were collected at a single timepoint from 250 patients with ONFH who were treated at our medical centre between July and December 2023 using validated instruments or, in the case of hip pain, a numerical rating scale. Factors associated with pain severity were identified using hierarchical multifactor linear regression. Results. Regression identified the following characteristics as independently associated with higher pain score, after adjustment for potential confounders: Association Research Circulation Osseous classification stage IIIa or IIIb, bone marrow oedema, grade 3 joint effusion, as well as higher scores on pain catastrophizing, anxiety, and central sensitization. The final model explained 69.7% of observed variance in pain scores, of which clinical and radiological factors explained 37%, while psychological and neurophysiological factors explained 24% and demographic factors explained 8.7%. Conclusion. Multidimensional characteristics jointly contribute to the severity of pain associated with ONFH. These findings highlight the need to comprehensively identify potential contributors to pain, and to personalize management and treatment accordingly. Cite this article: Bone Joint Res 2024;13(11):673–681

Background. Exebacase, an antistaphylococcal lysin in Phase 3 of development as a treatment for S. aureus bacteremia/right-sided endocarditis has demonstrated antibiofilm activity in vitro and has previously been used as salvage therapy in four patients with relapsing multidrug-resistant (MDR) S. epidermidis knee prosthetic joint infection (PJI) using a procedure called LysinDAIR (administration of the lysin during the performance of an arthroscopic DAIR). Materials/methods. We performed a single center, exploratory, open-label prospective study using the LysinDAIR procedure in patients with chronic (inoculation >3 months prior to treatment) coagulase-negative staphylococci (CNS) PJI of the knee with two different clinical presentations and treatment paradigms. Cohort A: first episode of CNS knee PJI, for whom the LysinDAIR was followed by clindamycin + levofloxacin planned to be prescribed for three months and then stopped; and Cohort B: relapsing episodes of MDR CNS knee PJI for whom the LysinDAIR was followed by primary antimicrobial therapy for three months, followed by suppressive antimicrobial therapy (SAT). Exebacae susceptibility testing was performed before treatment for each patient. In agreement with the French Health authority, exebacase (2 to 3.5 total mg in 30–50 ml (∼0.067 – 0.075 mg/m) was administered directly into the joint during arthroscopy. Results. Eight patients were treated. Exebacase administration was well tolerated by all patients and no serious adverse drug reactions to exebacase were reported. In cohort A (n=4), patients had susceptible S. epidermidis PJI, a painful joint effusion without fistula and without loosening, and received three months of levofloxacin + clindamycin (one patient received an alternative regimen following antibiotic adverse events) and then antibiotics were stopped. During a follow-up of 14, 19, 26 and 36 months, no relapse, no recurrence of the joint effusion and no loosening occurred. In cohort B (n=4), patients had MDR CNS, clinical signs of septic arthritis with a joint effusion without fistula and without loosening and received daptomycin + linezolid or doxycycline. One patient died from COVID-19 at week 4. SAT (tedizolide, n=2; doxycycline, n=1) was then prescribed to other patients. One experienced an infection relapse involving S. caprae under tedizolid therapy at six months. The two other patients continue to do well under SAT 8 and 12 months after the LysinDAIR procedure. Conclusions. The LysinDAIR procedure is a minimally invasive procedure, which has been shown to be easy-to-perform, safe, and has the potential for use as initial treatment or salvage therapy in patients with CNS chronic knee PJI

Abstract. Introduction. The aim of this study was to determine the factors affecting return to sport (RTS) and career longevity of elite athletes after microfracture of the knee. Methods. A retrospective review of a consecutive series of elite athletes with chondral injuries in the knee treated with microfracture was undertaken. RTS was defined as competing in at least one event at professional level or national/ international level in amateur sport. Demographic, pre, intra and post operative factors affecting RTS were analysed. Results. Fifty six athletes, including 35 (62.5%) footballers and 14 (25.0 %) rugby players, with a mean age 24.8 (+/− 3.9) years, were included. 18 (32.1 %) of chondral injuries were secondary to trauma, 20 (35.7 %) post meniscectomy, 9 (16.1%) post anterior cruciate ligament (ACL) reconstruction and 9 (16.1%) idiopathic. Fifty (89.3%) of athletes RTS at a mean time of 10.0 (+/−5.8) months. 43 (86.0%) athletes were still playing at 2 years. At 5 years 25 (59.5%) of the players who had RTS and had surgery more than 5 years ago were still playing professional sport. Factors associated with not playing at 5 years were cartilage lesions >1.5cm2(52.4% vs 66.7%), more than 1 lesion (35.7% vs74.1%), lateral meniscal surgery (42.1% vs 73.7%) and effusion on RTS (47.7% vs 72.2%). Conclusion. Over 89 % of elite athletes returned to professional sport after microfracture in the knee. However, the ability to continue playing is affected by several factors such as the extent of the chondral damage and recurrent effusions

Aims. There is insufficient evidence to recommend the use of alternative polyethylene bearings in modular, fixed-bearing total knee arthroplasty (TKA). The purpose of this study was to compare standard polyethylene (SP) and highly crosslinked polyethylene (XLP) tibial liners in posterior-stabilized TKA, with osteolysis as the primary outcome and clinical results and the rate of re-operation as the secondary outcomes. Patients and Methods. This is a single-surgeon, prospective randomized study involving one design of modular posterior-stabilized TKA. An analysis of 122 TKAs with an SP compression moulded liner and 123 with an XLP liner was performed, with a mean follow-up of six years (2 to 11). Patients were evaluated clinically using the Knee Society score, Lower Extremity Activity Score (LEAS), and the presence of an effusion, and standard radiographs were assessed for radiolucent lines and osteolytic lesions. Results. Osteolysis was present in four TKAs (3.3%) in the SP group, and no knees in the XLP group (p = 0.06). There were no significant differences between the Knee Society total score, change in total score, knee function score, change in function score, LEAS, and change in LEAS in the two groups. There was a significant difference in the presence of an effusion (10/122 with SP liners, 1/123 with XLP liners; p = 0.02). There was no significant difference in the rate of re-operation between the two groups (p = 0.36). There were no complications related to the XLP liner. Conclusion. At this length of follow-up, there were no advantages and no complications related to the use of this XLP tibial liner. The presence of effusion and small osteolytic lesions was more frequent with SP than XLP liners, but of unknown clinical significance. Cite this article: Bone Joint J 2019;101-B(7 Supple C):33–39

Aims. Temporary hemiepiphysiodesis (HED) is applied to children and adolescents to correct angular deformities (ADs) in long bones through guided growth. Traditional Blount staples or two-hole plates are mainly used for this indication. Despite precise surgical techniques and attentive postoperative follow-up, implant-associated complications are frequently described. To address these pitfalls, a flexible staple was developed to combine the advantages of the established implants. This study provides the first results of guided growth using the new implant and compares these with the established two-hole plates and Blount staples. Methods. Between January 2013 and December 2016, 138 patients (22 children, 116 adolescents) with genu valgum or genu varum were treated with 285 flexible staples. The minimum follow-up was 24 months. These results were compared with 98 patients treated with 205 two-hole plates and 92 patients treated with 535 Blount staples. In long-standing anteroposterior radiographs, mechanical axis deviations (MADs) were measured before and during treatment to analyze treatment efficiency. The evaluation of the new flexible staple was performed according to the idea, development, evaluation, assessment, long-term (IDEAL) study framework (Stage 2a). Results. Overall, 79% (109/138) of patients treated with flexible staples achieved sufficient deformity correction. The median treatment duration was 16 months (interquartile range (IQR) 8 to 21). The flexible staples achieved a median MAD correction of 1.2 mm/month/HED site (IQR 0.6 to 2.0) in valgus deformities and 0.6 mm/month/HED site (IQR 0.2 to 1.5) in varus deformities. Wound infections occurred in 1%, haematomas and joint effusions in 4%, and implant-associated complications in 1% of patients treated with flexible staples. Valgus AD were corrected faster using flexible staples than two-hole plates and Blount staples. Furthermore, the median MAD after treatment was lower in varus and valgus AD, fewer implant-associated complications were detected, and reduced implantation times were recorded using flexible staples. Conclusion. The flexible staple seems to be a viable option for guided growth, showing comparable or possibly better results regarding correction speed and reducing implant-associated complications. Further comparative studies are required to substantiate these findings. Cite this article: Bone Joint J 2023;105-B(3):331–340

Abstract. The Coronavirus pandemic mandated an immediate and dramatic change in the delivery of acute trauma services to minimise face-to-face contact. In our hospital, patients presenting to the Emergency Department with a knee injury and no fracture seen on Xrays were referred to a “Virtual Fracture Clinic” (VFC) where Xrays and clinical notes were reviewed by the duty Trauma and Orthopaedic Consultant the following working day. We present the outcomes of 101 consecutive patients managed through this process and deemed to have a “Soft Tissue Knee Injury” with a minimum follow-up of six months. All Xrays were reviewed by a sub-specialist knee surgeon blinded to notes or clinical outcomes. Electronic clinical records were reviewed to determine further clinical appointments, surgical treatment and pending interventions. Of 101 patients, the knee surgeon diagnosed 1 Fracture, 4 Lipo-haemarthroses, 41 significant effusions and 55 patients with normal Xrays. Correlation to urgent surgery was 100% for fracture (1/1), 25% for Lipo-haemarthrosis (1/4), 7.3% for significant effusion (3/41) and 9.1% for normal Xrays (5/55). A further 9.8% (4/41) of the “effusion” group and 7.3% (4/55) of the “normal” group were subsequently listed for non-urgent surgery. Overall 17% (7/41) of “effusion” patients and 16% (9/55) of “normal” patients required surgery. Management plans from VFC varied within groups. Acute “soft-tissue” injuries of the knee in adults cannot be reliably managed via VFC based on X-ray findings. A staged review by an appropriately trained health professional could reduce demand on acute knee surgical clinics and may enhance patient outcomes

Introduction. Closed suction intraarticular drain (CSD) use after total knee arthroplasty (TKA) has been studied with regards to wound healing and range of motion, however, no data exist on how CSD use impacts knee joint effusion and quadriceps strength. The primary purpose of this study was to determine whether CSD use influences recovery of quadriceps strength. Secondary outcomes examined effects of CSD on intraarticular effusion, lower limb swelling, knee range of motion (ROM), pain and wound healing complications. Methods. Twenty-nine patients undergoing same-day bilateral TKA were enrolled in a prospective, randomized blinded study. Subjects were randomized to receive a CSD on one lower extremity while the contralateral limb had the use of a subcutaneous drain (SCDRN) without the use of suction. Isometric quadriceps strength was collected as the primary outcome. Secondary outcomes consisted of quadriceps muscle activation, intraarticular effusion measured via ultrasound, lower extremity swelling measured with bioelectrical impendence, lower extremity girth, ROM, and pain. Outcomes were assessed preoperatively and postoperatively at day 2, 2 and 6 weeks and 3 months. Differences in limbs were determined using paired t-tests or Wilcoxon signed rank tests. Results. No significant differences were identified between limbs prior to surgery for the primary or secondary outcomes. No significant differences in quadriceps strength were seen between CSD and SCDRN limbs at postoperative day 2 (p = 0.09), two weeks (p=0.7), six weeks (p=0.3), or three months (p=0.5). Secondary outcomes, of quadriceps activation battery, intraarticular effusion, lower extremity swelling, ROM, and pain were not found to significantly differ at any time point following surgery. Conclusion. The use of CSD during TKA did not influence quadriceps strength, quadriceps activation, intraarticular effusion, bioelectrical measure of swelling, ROM, or pain. The results of this study have limited drain use by the authors in primary uncomplicated TKA

After knee replacement, therapy resistant, chronic synovitis is common and leads to effusion and pain. A cohort of 55 patients with 57 knee replacements and chronic synovitis underwent radiosynoviorthesis. In summary, 101 joints were treated using 182±9 MBq of 90Y-citrate. The number of radiosynoviorthesis ranged from 1 to 4 (53%, 21%, 23%, and 4%). Every patient received a 99mTc-MDP scintigraphy before and three months after every radiosynoviorthesis. Follow-up ranged from 5.7 to 86.7 months. For qualitative analysis, an four steps scoring was used (0 = no response or worsening, 1 = slight, 2 = good, 3 = excellent response). For quantification, the uptake was determined within the 99mTc-MDP scintigraphy soft tissue phase before and after therapy. At the end of long-term follow-up 27% of patients have an excellent, 24% good, 30% slight and 20% no response. The duration of response was 7.5±8.3 months (maximum 27 months). In repeated treatment, the effect after the first therapy was lesser than in patients who received a single treatment in total. However, three months after the last radiosynoviorthesis, patients with repeated treatment showed a similar effectiveness than single treated patients. At the end of long-term follow-up, patients with repeated radiosynoviorthesis had a higher effectiveness at similar duration response. In the 99mTc-MDP scan 65% of patients showed a reduction of uptake. When comparing subjective and objective response 78% of patients showed a concordance in both, symptoms and scintigraphy. Pilot histological analysis revealed that the synovitis is triggered by small plastic particles. Radiosynoviorthesis is effective in patients with knee replacement and chronic synovitis. It shows good subjective and objective response rates and long response duration. Repeated treatment leads to a stronger long-time response. The chronic synovitis is caused by plastic particles, which result from the abrasion of the polymeric inlay of endoprothesis

Aims. To analyze the potential role of synovial fluid peptidase activity as a measure of disease burden and predictive biomarker of progression in knee osteoarthritis (KOA). Methods. A cross-sectional study of 39 patients (women 71.8%, men 28.2%; mean age of 72.03 years (SD 1.15) with advanced KOA (Ahlbäck grade ≥ 3 and clinical indications for arthrocentesis) recruited through the (Orthopaedic Department at the Complejo Asistencial Universitario de León, Spain (CAULE)), measuring synovial fluid levels of puromycin-sensitive aminopeptidase (PSA), neutral aminopeptidase (NAP), aminopeptidase B (APB), prolyl endopeptidase (PEP), aspartate aminopeptidase (ASP), glutamyl aminopeptidase (GLU) and pyroglutamyl aminopeptidase (PGAP). Results. Synovial fluid peptidase activity varied significantly as a function of clinical signs, with differences in levels of PEP (p = 0.020), ASP (p < 0.001), and PGAP (p = 0. 003) associated with knee locking, PEP (p = 0.006), ASP (p = 0.001), GLU (p = 0.037), and PGAP (p = 0.000) with knee failure, and PEP (p = 0.006), ASP (p = 0.001), GLU (p = 0.037), and PGAP (p < 0.001) with knee effusion. Further, patients with the greatest functional impairment had significantly higher levels of APB (p = 0.005), PEP (p = 0.005), ASP (p = 0.006), GLU (p = 0.020), and PGAP (p < 0.001) activity, though not of NAP or PSA, indicating local alterations in the renin-angiotensin system. A binary logistic regression model showed that PSA was protective (p = 0.005; Exp (B) 0.949), whereas PEP (p = 0.005) and GLU were risk factors (p = 0.012). Conclusion. These results suggest synovial fluid peptidase activity could play a role as a measure of disease burden and predictive biomarker of progression in KOA. Cite this article: Bone Joint Res 2020;9(11):789–797

Background. Bacteriophages are natural viruses of interest in the field of PJI. A paper previously reported the PhagoDAIR procedure (use of phages during DAIR) in three patients with PJI for whom explantation was not desirable. As the need to isolate the pathogen before surgery to perform phage susceptibility testing is a strong hindrance for the development of this procedure, we developed post-operative phage injections using ultrasound, in patients infected with S. aureus and/or P. aeruginosa who were eligible for the PhagoDAIR procedure, but for whom phages were not available at the time of surgery. Materials/Methods. We performed a single center, exploratory, prospective cohort study including patients with knee PJI who received phage therapy with ultrasound after performance of a DAIR or a partial prosthesis exchange. All patients had PJI requiring conservative surgery and suppressive antimicrobial therapy (SAT) as salvage procedure. Each case was discussed in multidisciplinary meetings in agreement with French health authority, based on the clinical presentation, and the phage susceptibility testing. The cocktail of highly concentrate active phages (5 mL; about 10. e. 9 PFU/mL) was extemporaneous prepared and administered three times directly into the joint using sonography (1 injection per week during 3 weeks) during the postoperative period, before switching antibiotics to SAT. Results. Seven patients received phages under sonography after the DAIR, and one after a partial exchange (mean age 71 years). All had resection prosthesis or constrained knee prosthesis. Among these seven patients, three were infected with S. aureus (including one MRSA), two were infected with P. aeruginosa (one was a multidrug-resistant isolate), one was infected with both S. aureus and P. aeruginosa and the last one was infected with MRSA, S. epidermidis and Corynebacterium spp.. All patients received a cocktail of active phages provided by Pherecydes Pharma targeting S. aureus or P. aeruginosa. No adverse event was recorded during or after the local injections. All patients were switched to SAT after a primary postoperative antimicrobial therapy of three months. Under SAT, the patient with S. epidermidis co-infection developed a relapse due to the S. epidermidis. With a mean follow-up of 13 months after surgery (from 9 to 24 months), the outcome was favorable for all patients without any sign of infection; none of them had abnormal pain, joint effusion or loosening. Conclusions. Postoperative administration of phages using sonography is a potentially useful procedure in patients with complex PJI for whom a conservative approach is desirable