Low percentage of patients passed the 'Back in Action' test battery 9 months after bone-patellar tendon-bone anterior cruciate ligament reconstruction.

Background: Anterior cruciate ligament (ACL) reconstruction is recommended in patients who intend to return to high-level sports. However, there is only a 55-80% return to pre-injury level of sports after ACL reconstruction, with a re-injury rate up to 20%. The aim of this study was to determine the percentage of patients passing the Back in Action (BIA) test 9 months after primary bone-patellar-tendon-bone (BPTB) ACL reconstruction, and evaluate the association between passing the BIA test and patient reported outcome measurements (PROMs). Methods: Patients underwent the BIA test 9 months after BPTB ACL reconstruction. In total 103 patients were included. Passing the BIA test (PASSED-group) was defined as a normal or higher score at all sub-tests with limb symmetry index (LSI) ≥90% for the dominant leg and LSI >80% for the non-dominant leg. Patients who did not meet these criteria were defined as the FAILED-group. PROMs included the International Knee Documentation Committee, Knee injury Osteoarthritis Outcome Score and Anterior Cruciate Ligament-Return to Sport after Injury. Results: Eighteen patients (17.5%) passed the BIA test 9 months after BPTB ACL reconstruction. PROMs were not statistically significant different between the PASSED- and FAILED-group. Conclusion: Low percentage of patients passed the BIA test 9 months after BPTB ACL reconstruction. Although current PROMs cut-off values were met, the BIA test results show persistent functional deficits. Therefore, the BIA test could be of additional value in the decision-making process regarding return to sport (RTS). This study highlights the need for additional rehabilitation as RTS in a condition of incomplete recovery may increase the risk of re-injury. Level of evidence: II.

Effect of Low-Load Blood Flow Restriction Training After Anterior Cruciate Ligament Reconstruction: A Systematic Review.

Background: Quadriceps strength and mass deficits are common after anterior cruciate ligament (ACL) reconstruction. Postoperatively, heavy load resistance training can have detrimental effects on knee joint pain and ACL graft laxity. Therefore, low-load blood flow restriction (LL-BFR) training has been suggested as an alternative to traditional strength rehabilitation. Purpose: The present systematic review aimed to investigate the effect of LL-BFR training on quadriceps strength, quadriceps mass, knee joint pain, and ACL graft laxity after ACL reconstruction compared to non-BFR training. Study design: Systematic review. Methods: A systematic literature search of PubMed, EMBASE.com, Cochrane Library/Wiley, CINAHL/Ebsco and Web of Science/Clarivate Analytics was performed on 19 February 2021. Studies were included if they compared LL-BFR and non-BFR training after ACL reconstruction with pre- and post-intervention quadriceps strength, quadriceps mass, knee joint pain or ACL graft laxity measurement. Systematic reviews, editorials, case reports and studies not published in a scientific peer reviewed journal were excluded. The risk of bias of randomized studies was assessed with the use of the Cochrane Risk of Bias Tool. Results: A total of six randomized controlled trials were included. Random sequence generation and allocation concealment was defined as high risk in two of the six studies. In all studies blinding of participants and personnel was unclear or could not be performed. The included studies used different LL-BFR and non-BFR protocols with heterogeneous outcome measurements. Therefore, a qualitative analysis was performed. Two of the six studies assessed quadriceps strength and demonstrated significant greater quadriceps strength after LL-BFR compared to non-BFR training. Quadriceps mass was evaluated in four studies. Two studies observed significant greater quadriceps mass after LL-BFR compared to non-BFR training, while two studies observed no significant difference in quadriceps mass. Knee joint pain was assessed in three studies with significantly less knee joint pain after LL-BFR compared to non-BFR training. Two studies evaluated ACL graft laxity and observed no significant difference in ACL graft laxity between LL-BFR and non-BFR training. Conclusion: The results of this systematic review indicate that LL-BFR training after ACL reconstruction may be beneficial on quadriceps strength, quadriceps mass, and knee joint pain compared to non-BFR training with non-detrimental effects on ACL graft laxity. However, more randomized controlled trials with standardized intervention protocols and outcome measurements are needed to add evidence on the clinical value of LL-BFR training. Level of evidence: 2a.

Predictors of patient satisfaction after primary hamstring anterior cruciate ligament reconstruction.

BACKGROUND: Predictors of patient satisfaction (PS) after anterior cruciate ligament (ACL) reconstruction are not well known. This study investigated predictors of PS and whether PS was associated with pre-injury level of sport participation, patient reported knee function and quality of life after ACL reconstruction. METHODS: Patients who underwent primary hamstring ACL reconstruction between January 2015 and December 2017 were retrospectively evaluated. An online survey was used to evaluate PS (yes = satisfied, no = unsatisfied), duration of supervised postoperative rehabilitation, timing of return to pre-injury level of sport, pre-injury level of sport participation, patient reported knee function and quality of life. Preoperative, operative and postoperative variables were collected from the medical records. RESULTS: A total of 183 patients completed the survey at a median of 3.6 (1.5) years after ACL surgery. At final follow-up, 82% of patients were satisfied with the outcome. Preoperative (e.g. age) and operative (e.g. meniscal tear) variables were not predictors of PS (p > 0.05). Duration of supervised postoperative rehabilitation, timing of return to pre-injury level of sport and postoperative ACL injury were predictors of PS (p = 0.018, p = 0.016 and p < 0.001, respectively). Pre-injury level of sport participation was significantly higher in satisfied compared to unsatisfied patients: 44.7% (n = 67) versus 18.2% (n = 6) (p = 0.005). In addition, satisfied patients reported significantly higher patient reported knee function and quality of life compared to unsatisfied patients (p < 0.001). CONCLUSION: This study provided data on predictors of PS after primary ACL reconstruction. Furthermore, PS was associated with pre-injury level of sport participation, patient reported knee function and quality of life.

Preferences in anterior cruciate ligament reconstruction and return to sport: A survey among surgeons in the Netherlands.

OBJECTIVE: The purpose of this study was to investigate the preferences of surgeons on technique for femoral tunnel placement, graft selection and criteria for return to sport in the Netherlands. METHODS: A web-based survey among the Dutch Association of Arthroscopy was conducted. RESULTS: A total of 125 members (24.0%) were included in the analysis. A total of 87.2% (n = 109) used hamstring autografts for primary ACL reconstruction followed by patellar tendon autograft (n = 11, 8.8%) and quadriceps tendon autograft (n = 5, 4.0%). The anteromedial technique was favored by 50.4% (n = 63), whereas 11.2% (n = 14) of the participants favored the transtibial technique. Return to sport after 9 months of primary ACL reconstruction was allowed by 75.2% (n = 94) of the participants. Regarding criteria to evaluate readiness to return to sport, the surgeons stated postoperative period (n = 107, 85.6%) and functional performance tests (n = 96, 76.8%) as important. CONCLUSION: The majority of the participants of the Dutch Association of Arthroscopy favored the hamstring autografts for primary anterior cruciate ligament reconstruction. Furthermore, most participants stated postoperative time and functional performance tests as important criteria to evaluate readiness to return to sport. This is the first survey demonstrating a high preference of surgeons to use functional performance tests in the decision-making of readiness to return to sport.

High intra- and inter-observer reliability of planning implant size in MRI-based patient-specific instrumentation for total knee arthroplasty.

PURPOSE: Patient-specific instrumentation (PSI) in total knee arthroplasty (TKA) uses individually designed disposable guides to determine intraoperative bone cuts. The manufacturer provides the surgeon with proposed planning which can be modified and should be approved by the surgeon before the guides are produced. This study aims to assess the intra- and inter-observer reliability among preoperative planning by orthopaedic surgeons using PSI. The authors hypothesize a high intra- and inter-observer reliability in planning TKA using PSI. METHODS: Four orthopaedic surgeons modified and approved 40 preoperative MRI-based PSI plannings three times. The surgeons were blinded to their own and each other's results. Intra- and inter-observer reliability was obtained for planned implant size, resection, and position of the implant. RESULTS: Intra-observer reliability Intraclass Correlation Coefficients (ICC) were excellent for femoral and tibial implant size with a range of 0.948-0.995 and 0.919-0.988, respectively. Inter-observer reliability for femoral and tibial implant size showed an ICC range of 0.953-0.982 and 0.839-0.951, respectively. Next to implant size, intra- and inter-observer reliability demonstrated good to an excellent agreement (ICC > 0.75) for 7 out of 12 remaining parameters and 6 out of 12 remaining parameters, respectively. CONCLUSION: Preoperative planning of TKA implant size using MRI-based PSI showed excellent intra- and inter-observer reliability. Further research on the comparison of predicted implant size preoperatively to intraoperative results is needed.

Mechanoreceptors observed in a ligamentous structure between the posterior horn of the lateral meniscus and the anterior cruciate ligament.

PURPOSE: A histological study of a structure between the posterior horn of the lateral meniscus and the anterior cruciate ligament. METHODS: Bilateral fresh-frozen cadaveric knees of two male donors (age 71 and 76 years) with no history of prior knee injury were examined. All dissections were performed by one experienced orthopaedic surgeon. Haematoxylin and Eosin staining was used to reveal tissue morphology. Goldner trichrome staining was used to evaluate the connective tissue. S100 and PGP 9.5 labelling were used for immunohistochemical analysis. RESULTS: In all cadaveric knees, a structure between the posterior horn of the lateral meniscus and the anterior cruciate ligament was identified. Histological analysis confirmed the ligamentous nature of this structure. Furthermore, Golgi tendon organs were observed within the ligamentous structure. CONCLUSION: This is the first study showing the presence of mechanoreceptors within the ligamentous structure between the posterior horn of the lateral meniscus and the anterior cruciate ligament. The ligamentous structure could contribute to stability of the knee by providing proprioceptive input, while preservation of the ligamentous structure might ensure a better functional outcome after surgery.

The Dutch version of the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form is a reliable and valid questionnaire for shoulder problems.

BACKGROUND: The self-assessment section of the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASESq) is one of the most used patient-reported outcome measures for general shoulder problems. This study was performed to establish a valid Dutch version of the ASESq (ASESq-NL). MATERIALS AND METHODS: A clinical prospective, nonrandomized study was performed. Translation of the ASESq into Dutch was done following the guidelines of cross-cultural adaptation. Patients older than 17 years of age with shoulder problems were included. Patients who declined to participate or insufficiently completed questionnaires were excluded. For test-retest reliability analysis, the intraclass correlation coefficient (ICC) was calculated and an interval of 7-28 days between test and retest was set. Cronbach alpha was used to determine internal consistency. Dutch validated versions of the Shoulder Pain and Disability Index (SPADI) and 36-Item Short Form Health Survey (SF-36) were completed and compared with the ASESq-NL to evaluate construct validity using a Spearman rank correlation coefficient calculation. RESULTS: A total of 92 patients were included. Test-retest reliability was excellent with an ICC of 0.82. The mean test-retest interval was 13 days (standard deviation 4.4). Internal consistency was good, with a Cronbach alpha of 0.83. Construct validity of the ASES questionnaire was good. All domains of the ASESq-NL had significant (P < .05) correlations with the domains of the SPADI and the SF-36, except for the SF-36 domains stability with "physical function and energy" and "emotional well-being." CONCLUSION: The Dutch ASES questionnaire is a valid and reliable tool for the evaluation of shoulder problems and is permissible for implementation into the Dutch health care system.

Effectiveness of Early Warming With Self-Warming Blankets on Postoperative Hypothermia in Total Hip and Knee Arthroplasty.

BACKGROUND: Hypothermia is an important complication in joint arthroplasty. Commonly, forced air warming (FAW) devices are used intraoperatively to maintain body temperature in patients undergoing surgery. However, it is believed that these convective warming systems could increase the risk of deep surgical site infections due to disruption of unidirectional downward laminar airflow. Conductive warming devices have no noticeable effect on ventilation airflow. Nevertheless, the effectiveness of the self-warming (SW) blanket, a novel conductive warming device, on postoperative hypothermia in elective joint arthroplasty is unknown. PURPOSE: The purpose of this study was to evaluate the effectiveness of early warming with SW blankets in the prevention of postoperative hypothermia in elective total hip (THA) and knee arthroplasty (TKA) compared with FAW devices. METHODS: Patients who underwent elective THA or TKA between May and June 2014 were assigned in the FAW or SW group. A total of 105 patients were enrolled into the study. In the FAW group, the FAW devices were applied after disinfection of the surgical site. In the SW group, the SW blankets were already applied in the orthopaedic department. The duration of warming with SW blankets before anesthetic induction was documented. The body temperature was measured preoperatively upon arrival in the orthopaedic department and postoperatively upon arrival in the postanesthesia care unit. The patient's body temperature was measured at the tympanic membrane, and hypothermia was defined as a body temperature of less than 35.5°C. RESULTS: The SW blankets were applied for a median of 86.8 minutes (78.8-94.8) before anesthetic induction. Postoperative hypothermia was observed in 15 (31.3%) and eight (14.0%) patients in the FAW group and the SW group, respectively (p = .029). The median postoperative body temperature was 35.59°C (35.44-35.74) and 35.95°C (35.83-36.06) in the FAW group and the SW group, respectively (p < .001). CONCLUSION: Early warming with SW blankets was more effective than FAW devices in the prevention of postoperative hypothermia in elective THA and TKA.

Endoscopic debridement and fibrin glue injection of a chronic Morel-Lavallée lesion of the knee in a professional soccer player: A case report and literature review.

A Morel-Lavallée lesion is a post-traumatic closed degloving injury of soft tissue. The lesion is due to a shearing trauma with separation of subcutaneous tissue from underlying fascia. When conservative treatment fails, surgical treatment is imperative. Commonly, open drainage and debridement is performed. This case report describes a Morel-Lavallée lesion of the knee in a professional soccer player who was successfully treated with endoscopic debridement and fibrin glue injection after failure of conservative management. This method achieves the goal of an open surgical debridement without exposing patients to an increased morbidity.

Rickets in the Benelux. A case report of two Indian immigrants.

The last decades showed a resurgence of rickets and osteomalacia in the developed countries. In this report, we present two cases of dietary rickets in Indian teenage brothers who migrated to Europe. Supplementation of calcium and vitamin D3 to their diet resulted in rapid relief of musculoskeletal symptoms.

PEOT/PBT based scaffolds with low mechanical properties improve cartilage repair tissue formation in osteochondral defects.

The aim of our study was to compare the healing response of biomechanically and biochemically different scaffolds in osteochondral defects created in rabbit medial femoral condyles. A block copolymer comprised of poly(ethylene oxide terephthalate) and poly(butylene terephthalate) was used to prepare porous scaffolds. The 70/30 scaffold (70 wt % poly(ethylene oxide terephthalate)) was compared to the stiffer 55/45 (55 wt % poly(ethylene oxide terephthalate)) scaffold. Nine 6-month-old rabbits were used. Osteochondral defects were filled with 55/45 scaffolds (n = 6); 70/30 scaffolds (n = 6); or left empty (n = 6). Defect sites were allowed to heal for 12 weeks. Condyles were macroscopically evaluated and analysed histologically using the O'Driscoll score for evaluating repair of osteochondral defects. Repair tissue in 70/30 scaffolds consisted of cartilage-like tissue on top of trabecular bone, whereas the tissue within the 55/45 scaffolds consisted predominantly of trabecular bone. O'Driscoll scores for 70/30 scaffolds were significantly better (p = 0.024) in comparison to untreated osteochondral defects and 55/45 scaffolds. This study reveals that the biomechanical and biochemical properties of the scaffold play an important role by themselves, and can affect the healing response of osteochondral defects. Scaffolds with low mechanical properties were superior in cartilage repair tissue formation.

Human periosteum-derived cells from elderly patients as a source for cartilage tissue engineering?

The aim of this study was to establish the potential of human periosteum-derived cells from elderly patients as a cell source for cartilage tissue engineering by optimizing culture conditions for both proliferation and differentiation. Periosteum was obtained from the tibiae of nine patients. Biopsies were prepared for routine histological examination. Periosteum-derived cells were allowed to grow out from the remaining tissue, and were expanded in minimum essential medium containing D-valine (MEM-DV). Fetal bovine serum (FBS) or substitutes, fibroblast growth factor-2 (FGF-2), insulin-like growth factor-1 (IGF-1) and non-essential amino acids were added to study proliferation. For differentiation of cells, serum-free medium was used supplemented with one or more isoforms of transforming growth factor-beta (TGFbeta) and/or IGF-1. Samples were analysed for expression of collagens type I, II and X by competitive RT-PCR, immunohistochemically, and histologically using Alcian blue staining. In all samples the cambium layer could hardly be detected. Periosteum-derived cells proliferated in serum-containing MEM-DV. Optimal proliferation was found when this medium was supplemented with 100 ng/ml FGF-2 and non-essential amino acids. Chondrogenesis was detected in 59% of micromasses that were cultured with TGFbeta isomers, and in 83% of the samples cultured in media to which two TGFbeta isoforms were added. Periosteum from elderly humans (mean age 66, range 41-76 years) has chondrogenic potential and remains an attractive cell source for cartilage tissue engineering. By expanding cells in MEM-DV, the selection of progenitor cells might be favoured, which would result in a higher cartilage yield for tissue engineering applications.

One intra-articular injection of hyaluronan prevents cell death and improves cell metabolism in a model of injured articular cartilage in the rabbit.

The purpose of this study was to determine the effect of one intra-articular injection of hyaluronan on chondrocyte death and metabolism in injured cartilage. Twenty-three 6-month-old rabbits received partial-thickness articular cartilage defects created on each medial femoral condyle. In order to examine the effect on articular cartilage surrounding iatrogenic cartilage lesions, which can occur during arthroscopic procedures, Study 1 was performed: in 14 rabbits both knees were immediately rinsed with 0.9% NaCl. Experimental knees were treated with hyaluronan. Six rabbits were sacrificed at 2 days; eight rabbits 3 months postoperatively. Histomorphometric analysis was used for studying cell death in cartilage next to the defect. In order to examine the effect on longer lasting lesions, more reflecting the clinical situation, Study 2 was performed: after 6 months knee joints of nine rabbits were (i) irrigated with 0.9% NaCl, (ii) treated with hyaluronan after irrigation with 0.9% NaCl, or (iii) sham-treated. After 7 days patellas were used to study the chondrocyte metabolism by measuring the [(35)S]sulfate incorporation. Study 1: Two days postoperatively, in hyaluronan-treated cartilage the percentage of dead cells was 6.7%, which was significantly lower compared to 16.2% in saline-treated cartilage. After 3 months the percentages of dead cells in both groups were statistically similar. Study 2: Hyaluronan treatment resulted in significantly higher [(35)S]sulfate incorporation compared to knees irrigated with 0.9% NaCl. These results suggest a potential role for hyaluronan in preventing cell death following articular cartilage injury. One injection of hyaluronan improved cartilage metabolism in knees with 6-month-old cartilage defects.

Assessing infection risk in implanted tissue-engineered devices.

Peri-operative contamination is the major cause of biomaterial-associated infections, highly complicating surgical patient outcomes. While this risk in traditional implanted biomaterials is well-recognised, newer cell-seeded, biologically conducive tissue-engineered (TE) constructs now targeted for human use have not been assessed for this possibility. We investigated infection incidence of implanted, degradable polyester TE scaffold biomaterials in rabbit knee osteochondral defects. Sterile, polyester copolymer scaffolds of different compositions and cell-accessible pore volumes were surgically inserted into rabbit osteochondral defects for periods of 3 weeks up to 9 months, either with or without initial seeding with autologous or allogeneic chondrocytes. Infection assessment included observation of pus or abscesses in or near the knee joint and post-mortem histological evaluation. Of 228 implanted TE scaffolds, 10 appeared to be infected: 6 scaffolds without cell seeding (3.6%) and 4 cell-seeded scaffolds (6.3%). These infections were evident across all scaffold types, independent of polymer composition or available pore volume, and up to 9 months. We conclude that infections in TE implants pose a serious problem with incidences similar to current biomaterials-associated infections. Infection control measures should be developed in tissue engineering to avoid further complications when TE devices emerge clinically.

Hydrophobicity as a design criterion for polymer scaffolds in bone tissue engineering.

Porous polymeric scaffolds play a key role in most tissue-engineering strategies. A series of non-degrading porous scaffolds was prepared, based on bulk-copolymerisation of 1-vinyl-2-pyrrolidinone (NVP) and n-butyl methacrylate (BMA), followed by a particulate-leaching step to generate porosity. Biocompatibility of these scaffolds was evaluated in vitro and in vivo. Furthermore, the scaffold materials were studied using the so-called demineralised bone matrix (DBM) as an evaluation system in vivo. The DBM, which is essentially a part of a rat femoral bone after processing with mineral acid, provides a suitable environment for ectopic bone formation, provided that the cavity of the DBM is filled with bone marrow prior to subcutaneous implantation in the thoracic region of rats. Various scaffold materials, differing with respect to composition and, hence, hydrophilicity, were introduced into the centre of DBMs. The ends were closed with rat bone marrow, and ectopic bone formation was monitored after 4, 6, and 8 weeks, both through X-ray microradiography and histology. The 50:50 scaffold particles were found to readily accommodate formation of bone tissue within their pores, whereas this was much less the case for the more hydrophilic 70:30 counterpart scaffolds. New healthy bone tissue was encountered inside the pores of the 50:50 scaffold material, not only at the periphery of the constructs but also in the center. Active osteoblast cells were found at the bone-biomaterial interfaces. These data indicate that the hydrophobicity of the biomaterial is, most likely, an important design criterion for polymeric scaffolds which should promote the healing of bone defects. Furthermore, it is argued that stable, non-degrading porous biomaterials, like those used in this study, provide an important tool to expand our comprehension of the role of biomaterials in scaffold-based tissue engineering approaches.