Raúl Torres-Claramunt

Use of antibiotic-loaded cement in total knee arthroplasty

Bone cement has the capacity to release antibiotic molecules if any antibiotic is included in it, and these elution properties are improved as cement porosity is increased. In vitro studies have shown high local antibiotic concentration for many hours or few days after its use. Antibiotic loaded bone cement (ALBC) is helpful when treating an infection in total knee arthroplasty (TKA) revision surgery. The purpose of this paper was to review the evidence for the routine use of ALBC in TKA in the literature, its pros and cons. Many authors have recommended the use of ALBC also in primary TKA for infection prophylaxis, but the evidence based on data from National Registries, randomized clinical trials and meta-analysis suggest a protective effect of ALBC against infection when used in hips, but not (or only mild) in knees. A possible explanation to this finding is that the duration and quantity of locally elevated antibiotic levels after surgery are smaller in TKA, due to the smaller amount of cement used for fixation in TKA-only a layer in the bone surface. There are some concerns about the routine use of ALBC in primary TKA as prophylaxis against infection: Firstly, there is a risk of hypersensivity or toxicity even when the chance is highly improbable. Secondly, there is a reduction in the mechanical properties of the cement, but this can be probably neglected if the antibiotic is used in low doses, not more than 1 g per 40 g cement package. Another significant concern is the increased economic cost, which could be overlooked if there were enough savings in treating fewer prosthetic infections. Finally, there is also a risk of selection of antibiotic-resistant strains of bacteria and this could be the main concern. If used, the choice of the antibiotic mixed in ALBC should consider microbiological aspects (broad antimicrobial spectrum and low rate of resistant bacteria), physical and chemical aspects (thermal stability, high water solubility), pharmacological characteristics (low risk to allergic reactions or toxicity) and economic aspects (not too expensive). The most commonly used antibiotics in ALBC are gentamicin, tobramycin and vancomycin. In conclusion, there is a paucity of randomized clinical trials in the use of ALBC in primary TKAs and the actual evidence of the effect of ALBC in reducing the risk of infection is insufficient. This, in addition to concerns about patient safety, risks of increase in the antibiotic resistance of microorganisms and the increase in costs in the procedure, lead us to recommend a cautious use of ALBC, perhaps only in high-risk patients (immunocompromised, morbidly obese, diabetic and patients with previous history of fracture or infection around the knee) unless the benefits of ALBC use were fully proven. Meanwhile, the rigorous use of peri-operative prophylactic systemic antibiotics and adoption of efficient antiseptic procedures and improved surgical techniques must be considered the gold standard in infection prevention in TKA surgery.

Correlation Study Between KSS, WOMAC and SF-36 Scores in Patients Undergoing Total Knee Arthroplasty in a Spanish Speaking Population

The aim of this study was to determine whether it is necessary to use the KSS, WOMAC and SF-36 scales in a Spanish speaking population. These 3 questionnaires were administered to 1000 consecutive patients in the TKA preoperative period. Pearsons correlation coefficient and coefficient of determination were obtained. 196 patients were excluded. A poor correlation was obtained comparing the different items of the different scores with each other. Only in 3 out of different comparisons performed was a Pearsons correlation r>0.5 obtained. The worst results were obtained comparing the two knee specific tests (SF-36 vs WOMAC) and the best ones comparing SF-36 and WOMAC scores. Based on these results, the use of the three tests in the TKA preoperative period is recommended in a Spanish speaking population.

Long Term Follow-Up of Successfully Treated Superficial Wound Infections Following TKA

The relevance of wound complications in association with acute prosthetic joint infection (PJI) is well known. However, whether a successfully treated superficial infection can result in a chronic deep infection remains unclear. The aim of this study was to determine the prevalence, treatment and late complications of superficial wound infections following TKA. In a 3000 TKA prospective cohort, 45 superficial infections were diagnosed and treated successfully with antibiotic therapy along with or without surgical debridement. None of the cases developed deep chronic PJI at 70 months of follow-up. Three cases were in need of a TKA exchange due to aseptic loosening. A successfully treated superficial wound infection does not result in a chronic deep TKA infection.

Sealing of the intramedullar femoral canal in a TKA does not reduce postoperative blood loss: A randomized prospective study

BACKGROUND Sealing of the femoral canal, usually with autologous bone, is a surgical procedure that is often performed during TKA surgery to decrease blood loss in the postoperative period. However, evidence as to the effectiveness of this surgical procedure is not conclusive. The objective of this study was to assess the effectiveness of this surgical action in reducing postoperative blood loss and the blood transfusion rate. METHODS A randomized prospective study that included 201 TKAs divided into three groups (67 in each one) was carried out. The three groups were; A) bone graft sealing, B) cement sealing and C) unsealed canal. All groups were comparable with regard to pre and intra-operative data. The haemoglobin decrease at 2, 24 and 72 h was compared to the preoperative haemoglobin value. Subsequently, blood drainage at 12 and 24h and the rate of blood transfusion were also assessed. The different complications that arose were reported. RESULTS No statistical differences were obtained with regard to blood drainage at 12h (p=0.102) and 24h (p=0.542), the haemoglobin value decrease at 72 h (p=0.95) and the number of blood transfusions (p=0.597) in the three groups studied. CONCLUSION There was no significant difference, whether sealing the femoral canal with a bone graft, cement or when it was left unsealed, in decreasing blood loss or blood transfusion requirements in the postoperative period. LEVEL OF EVIDENCE Therapeutic type I.

Managing septic arthritis after knee ligament reconstruction.

PurposeJoint infection after anterior cruciate ligament (ACL) reconstruction is uncommon but has potentially serious consequences for the graft and articular cartilage. Most recently published series are in agreement that an urgent arthroscopic washout and antibiotic treatment are mandatory to preserve both graft and cartilage. However, several questions have not as yet been touched upon.MethodsWe performed a literature review to assess the most interesting series published about this issue.ResultsIn this review, a management protocol is first presented that discusses the different diagnostic parameters to consider and surgical and antibiotic treatment suggested according to the literature. Outcomes published in different series are also discussed.

Pressure algometry is a useful tool to quantify pain in the medial part of the knee: An intra- and inter-reliability study in healthy subjects

PURPOSE Pain quantification is essential for diagnostic and pain monitoring purposes in disorders around the knee. Pressure algometry is a method described to determine pressure pain threshold (PPT) by applying controlled pressure to a given body point. The purpose of this study was to determine the reliability of this method when it was applied to the medial part of the proximal tibia metaphysis and to evaluate the PPT levels between genders. METHODS Fifty healthy (mean age; 46.9) volunteers were recruited, 25 men and 25 women. Pressure algometry was applied to a 1 cm(2)-probe area on the medial part of the knee by 2 raters. Intra- and interclass correlation (ICC) was obtained and differences between genders were evaluated. Bland-Altman plots were performed to evaluate the variability of the measures. RESULTS The mean values of PPT obtained by rater 1 and 2 were 497.5 Kpa and 489 Kpa respectively. The intrarater reliability values (95% IC) for rater 1 and 2 were 0.97 (0.95-0.98) and 0.84 (0.73-0.90) respectively. With regard to interrater reliability, the ICC (95% IC) for the first measurement was 0.92 (0.87-0.95) and 0.86 (0.78-0.92) for the second one. Women showed significant lower values of PPT than men. The Bland-Altmand plots showed excellent agreement. CONCLUSIONS Pressure algometry has excellent reliability when it is applied to the medial part of the proximal metaphysis of the tibia. Women have lower values of PTT than men. The high reliability of the PA in an individual volunteer makes it a more valuable tool for longitudinal assessment of a given patient than for comparison between them. LEVEL OF EVIDENCE Level III. Prospective study.

Peri-operative Management in TKA

Total knee arthroplasty (TKA) has become the standard of care for patients with end-stage knee osteoarthritis (OA) and is one of the most frequently performed Orthopaedic procedures. Better knowledge of some complications that may occur in the TKA peri-operative period as they are infection, blood loss, thromboembolic events, and pain might allow for better management of the procedure from start to finish.

Partial quadriceps tendon transfer for revision medial patellofemoral ligament reconstruction: A new surgical technique

Medial patellofemoral ligament (MPFL) reconstruction for patellofemoral instability is a common procedure. Although MPFL reconstruction is a successful procedure in terms of return to normal life or sports, revision cases are challenging due to previous holes into the patella or implants placed in the anatomical femoral insertion site. In this technical note, the use of a partial quadriceps tendon transfer to the adductor magnus tendon is presented as a good solution for revision cases to avoid the use of implants, bone drilling, use of allografts, or two-stage surgical procedures. In addition, this procedure could be also used as a primary procedure in skeletally immature patients.

Pressure algometry is an excellent tool to measure knee pain relief after a closing-wedge high tibial osteotomy

PURPOSE The aim of this study was to assess the utility of pressure algometry (PA) to measure pain relief in the medial part of the knee after a closing-wedge high tibial osteotomy (CWHTO). METHODS Prospective study including 44 CWHTO. Pain relief was evaluated with the visual analogue scale (VAS) and PA, a radiological study was done and a functional assessment was carried out with the KSS preoperatively, at 6-months and at 1-year after the surgery. PA was applied to the medial and lateral part of the knee and to the infra-clavicular fossa as a control point. RESULTS The mechanical femorotibial angle was changed from 172.2° (SD2.2) to 180.6° (SD2.6) (p=0.00). KSS Knee improved from 53.4 (SD11.2) to 92.8 (SD7.3) (p=0.00), KSS Function from 69.4 (SD9.3) to 93.1 (SD8) (p=0.00). The VAS went from 6.84 (SD1.5) to 2.5 (SD2.1) (p=0.00) at the 1-year follow-up. The pressure pain threshold (PPT), measured with PA in the medial part of the knee also improved from 348.8kPa (SD159.3) to 447.1kPa (SD218.8) (p=0.01). However, the PPT in the lateral part of the knee and in the sub-clavicular fossa remained the same from the preoperative period to 6-months and 1-year, postoperatively. Neither were there any differences between the 6-month and 1-year postoperative values in terms of the different functional, radiological and pain relief obtained. CONCLUSION The pain relief obtained after a CWHTO in the medial part of the knee can be measured by using PA. Furthermore, the functional and pain improvement obtained at 1-year follow-up is no better than those obtained at 6-months postoperatively.

Discoid Meniscus. Meniscus Lesions in Children: Indications and Results

The discoid meniscus is an infrequent anatomical variant, which usually affects the lateral compartment of the knee. Its estimated prevalence is low and the higher rates have been observed in the Asian population. However, its actual frequency may be superior as has been described in various cadaveric studies. The most frequent clinical presentation is pain in the lateral knee compartment, and in only some cases is the classical snapping knee syndrome exhibited. The augmented thickness of the discoid menisci as well as its altered ultrastructure makes it more prone to tearing. Saucerization has been the classical surgical treatment. However, meniscal repair is preferred in children, particularly in the hypermobile Wrisberg type, when feasible. The long-term clinical results are good but signs of degenerative joint disease are frequently seen. Therefore, relative to meniscal removal, a conservative policy seems to be the most adequate option.