Knowledge-based, computerized, patient clinical decision support system for perioperative pain, nausea and constipation management: a clinical feasibility study.

Opioid administration is particularly challenging in the perioperative period. Computerized-based Clinical Decision Support Systems (CDSS) are a promising innovation that might improve perioperative pain control. We report the development and feasibility validation of a knowledge-based CDSS aiming at optimizing the management of perioperative pain, postoperative nausea and vomiting (PONV), and laxative medications. This novel CDSS uses patient adaptive testing through a smartphone display, literature-based rules, and individual medical prescriptions to produce direct medical advice for the patient user. Our objective was to test the feasibility of the clinical use of our CDSS in the perioperative setting. This was a prospective single arm, single center, cohort study conducted in Strasbourg University Hospital. The primary outcome was the agreement between the recommendation provided by the experimental device and the recommendation provided by study personnel who interpreted the same care algorithm (control). Thirty-seven patients were included in the study of which 30 (81%) used the experimental device. Agreement between these two care recommendations (computer driven vs. clinician driven) was observed in 51 out 54 uses of the device (94.2% [95% CI 85.9-98.4%]). The agreement level had a probability of 86.6% to exceed the 90% clinically relevant agreement threshold. The knowledge-based, patient CDSS we developed was feasible at providing recommendations for the treatment of pain, PONV and constipation in a perioperative clinical setting.Trial registration number & date The study protocol was registered in ClinicalTrial.gov before enrollment began (NCT05707247 on January 26th, 2023).

Early perioperative quality of recovery after hip and knee arthroplasty: a retrospective comparative cohort study.

PURPOSE: Increasing our knowledge about postoperative global Quality-Of-Recovery (QoR) after THA and TKA is important to improve perioperative medicine, in particular for preoperative patient information and benchmarking of postoperative patient status. METHODS: This study is a single centre, retrospective cohort study of prospectively collected data, conducted in Strasbourg University Hospital, Strasbourg, France. The main outcome was the modified French version of the QoR-15 (mQoR-15F) score monitored preoperatively, at postoperative day one, three, 14 and 28. We questioned the hypothesis: would THA and TKA recovery patterns differ and would postoperative health status eventually overreach the preoperative reference? RESULTS: The mQoR-15F was statistically higher in the THA group compared to the TKA group in POD 1 and 28 (112 ± 17 vs. 107 ± 17; p < 0.01 and 131 ± 12 vs. 127 ± 15; p = 0.02, respectively). The mean postoperative time delay to reach preoperative mQoR-15F was seven and 16 days for THA and TKA patients, respectively. CONCLUSION: Early postoperative health status after THA and TKA differs significantly; TKA being associated with a larger early decrease of global health status compared to THA. Both THA and TKA groups global health status overreached preoperative levels after one and two weeks postoperatively. These surgery-specific recovery profiles may favor improved patient information to steer advised operative decision and set specific recovery goals as part of enhanced recovery pathways.

The distal fibular perforating axial flap for lateral malleolus coverage: an anatomical description and surgical technique.

PURPOSE: Skin closure disorders in ankle surgery are a recurrent problem not only in traumatology but also in elective surgery. The aim of the study was to describe the anatomical basis of the fasciocutaneous vascularization of the lateral malleolus region to develop a posterior cover flap for the region. METHODS: We dissected ten fresh frozen specimens after arterial injection of an Indian ink preparation and individualized the perforating arteries. Their positions and diameters were collated. Then, the surgical technique was clinically applied for two different cases by transferring the fasciocutaneous flap posterior to the lateral malleolus to cover a loss of skin substance. RESULTS: There were in average 5 fibular perforators over the last 100 mm of the fibula. The average diameter of the first two perforating arteries was 0.6 ± 0.12 mm and 0.9 ± 0.25 mm, respectively, and the consistency of the latter makes it possible to produce a skin flap with anterior translation. This is an axial flap. Two patients were operated on using this technique. There was no necrosis of the posterior fibular flap and healing was achieved by the third post-operative week. CONCLUSION: This study showed the presence of fibular perforating arteries with a high reproducibility of their dissection. This anatomical description served as the basis for the description of a new distal fibular perforating flap.

Experimental study of risk of medial hinge fracture during distal femoral varus osteotomy.

INTRODUCTION: Lateral opening wedge distal femoral osteotomy (LOWDFO) is indicated for isolated lateral osteoarthritis in the valgus morphotype. Medial hinge fracture is a factor for poor prognosis. The present study had two aims: (1) to assess the impact of a temporary K-wire on hinge fracture risk; and (2) to assess the impact of LOWDFO opening speed. HYPOTHESIS: The main study hypothesis was that a temporary hinge K-wire reduces hinge fracture risk. The second hypothesis was that faster opening speed increases fracture risk. MATERIAL AND METHOD: Twenty femurs were produced by 3D printing from a CT database, reproducing LOWDFO anatomy. The ABS® polymer showed the same breaking-point behavior as human bone. Ten specimens were included in the "K-wire" group (KW+) and 10 in the "No K-wire" group (KW-). To determine high and low speed, a motion-capture glove was used by 2 operators, providing 3D modeling of the surgeon's hand. High speed was defined as 152mm/min and low speed as 38mm/min. The KW+ and KW- groups were subdivided into high- and low-speed subgroups (HS, LS) of 5 each. Compression tests were conducted using an Instron® mechanical test machine up to hinge fracture. The main endpoint was maximum breaking-point force (N); the secondary endpoints were maximum displacement (mm) and maximum speed (min) at breaking point. RESULTS: The K-wire significantly increased maximum breaking-point force (LS, 143.08N vs. 93.71N, p<0.01; and HS, 186.98N vs. 95.22N, p<0.01), but not maximum displacement (LS, 26.17mm vs. 24.11mm, p=0.31; and HS 26.18mm vs. 23.66mm, p=0.14) or maximum time (LS, 27.07s vs. 24.94s, p=0.31; and HS, 5.24s vs. 4.73s, p=0.14). Speed did not affect maximum force (KW+, 143.08N vs. 186.98N, p=0.06; and KW-, 93.71N vs. 95.22N, p=0.42) or maximum displacement (KW+, 26.17mm vs. 26.18mm, p=1; and KW-, 24.11mm vs. 23.66mm, p=0.69). Only maximum time was greater at low speed (KW+, 27.07s vs. 5.24s, p>0.01; and KW-, 24.94s vs. 4.73s, p<0.01), which is obvious for constant distance. DISCUSSION: The first study hypothesis was confirmed, with significantly lower hinge fracture risk with the K-wire, independently of opening speed. The second hypothesis was not confirmed. The study was performed under strict experimental conditions, unprecedented to our knowledge in the literature. However, complementary clinical studies are needed to confirm the present findings. LEVEL OF EVIDENCE: IV, experimental study.

Experimental investigation of the risk of lateral cortex fracture during valgus tibial osteotomy.

BACKGROUND: Valgus-producing medial opening-wedge proximal tibial osteotomies (V-MOW-PTO) are used to treat isolated medial-compartment knee osteoarthritis in patients with varus malalignment. A fracture of the lateral cortical hinge is a risk factor for poor outcomes. Implantation of a protective K-wire has been suggested to prevent this complication. The primary objective of this bench study was to assess the ability of a protective K-wire to prevent lateral cortical fractures. The secondary objective was to evaluate the influence of the opening speed on fracture risk during the osteotomy. HYPOTHESIS: The primary hypothesis was that a protective K-wire decreased the risk of hinge fracture. The secondary hypothesis was that this risk was greater when the opening speed was high. MATERIALS AND METHODS: We performed an experimental study of 20 simulated thermoplastic-polymer (ABS) tibias obtained by 3D printing to assess the effects of wedge-opening speed (high vs. low) and presence of a protective K-wire (yes vs. no). The opening rates were determined in a preliminary study of Sawbone® specimens opened using a distractor. The opening rate was measured using an accelerometer via a motion-capture glove. After assessing several high and low opening speeds, we selected 38mm/min and 152mm/min for the study. We divided the 20 ABS specimens into four groups of five each: high speed and K-wire, low speed and K-wire, high speed and no K-wire, and low speed and no K-wire. The force was applied using an Instron™ testing machine until construct failure. The primary outcome measure was the load at failure (N) and the secondary outcome measures were the displacement (mm) and maximum time to failure (s). RESULTS: At both speeds, values were significantly higher with vs. without a K-wire for load to failure (low: 253.3N vs. 175.5N, p<0.01; high: 262.2N vs. 154.1N, p<0.01), displacement (low: 11.1mm vs. 8.7mm, p<0.01; high: 11mm vs. 8.9mm; p=0.012), and maximal time to failure (low: 11.4 s vs. 8.9 s; p=0.012; high: 2.2 s vs. 1.8 s; p=0.011). Thus, the osteotomy opening speed seemed to have no influence on the risk of lateral cortex fracture. DISCUSSION: Our main hypothesis was confirmed but our secondary hypothesis was refuted: a protective K-wire significantly decreased the risk of hinge fracture, whereas the osteotomy opening speed had no influence. To our knowledge, this is the first published study assessing the potential influence of opening speed on risk of lateral cortex fracture. Our findings were obtained in the laboratory and should be evaluated in clinical practice. LEVEL OF EVIDENCE: IV, experimental study.

Comparison of five methods for locked-plate fixation of complex diaphyseal fractures.

BACKGROUND: Peri-prosthetic fractures (PPFs) are steadily rising in number due to population ageing and increased performance of joint replacement procedures. Although PPFs without implant loosening are usually managed by internal fixation, no consensus exists regarding the optimal construct. The primary objective of this study was to compare five constructs, and the secondary objective was to compare sub-groups of mono-cortical screw constructs, with the goal of identifying the method most appropriate for diaphyseal fracture fixation when prosthetic material is present within the intra-medullary canal. HYPOTHESIS: The primary hypothesis was that fixation using bi-cortical screws, i.e., the current reference standard, was superior over other fixation methods. The secondary hypothesis was that adding double cerclage to mono-cortical screw fixation provided the greatest mechanical strength. MATERIALS AND METHODS: Synthetic osteoporotic bone was used to compare five methods for locking-screw fixation of a femoral diaphyseal plate. One method involved bi-cortical screws and four methods mono-cortical screws, with no cerclage wire, a single cerclage wire on either side positioned near or at a distance from the fracture, and two cerclage wires on both sides of the fracture. A complex fracture was simulated by creating a 2-cm diaphyseal gap. Load-to-failure was determined by applying compression loading along the anatomical axis of the femur. RESULTS: Bi-cortical screw fixation provided greater mechanical strength than did three of the four mono-cortical screw constructs. The exception was the mono-cortical-screw and double-cerclage construct, for which no significant difference was found compared to bi-cortical screw fixation. Thus, mono-cortical screw fixation with double cerclage may be the best alternative when presence of an implant in the intra-medullary canal precludes bi-cortical screw fixation. CONCLUSION: The findings from this study have clear implications for clinical practice. The study hypotheses were partly confirmed. The absence of a significant difference between the reference-standard bi-cortical screw fixation method and mono-cortical screw fixation with double cerclage, combined with the results regarding the secondary objective, suggest that mono-cortical screws plus double cerclage deserve preference in patients with an intra-medullary implant. Clinical studies are needed to assess the results of this bench study. LEVEL OF EVIDENCE: IV, bench study.

Accuracy of the correction achieved after a valgus high tibial osteotomy: Comparison of the Hernigou table and navigation.

INTRODUCTION: The outcome of a medial opening wedge valgus high tibial osteotomy indicated for the treatment of isolated medial tibiofemoral osteoarthritis depends mainly on the accuracy of the correction of the hip-knee-ankle angle (HKAA) and the mechanical medial proximal tibial angle (mMPTA). Most authors aim for a desired correction target between 2° and 4° of valgus. Several planning and surgical techniques have been described to achieve this target value that is specific to each surgeon. OBJECTIVE: The purpose of this study was to compare the accuracy of the correction achieved using either the Hernigou table (HT) planning method or a computer-assisted navigation system (CAS). It was hypothesized that no difference would be found between these 2 techniques. MATERIALS AND METHODS: This retrospective single-center study involved 43 knees: 21 in the HT group and 22 in the CAS group. Two surgeons (ME, JYJ), who were experts in 1 of the 2 planning methods performed these procedures, with a single surgeon assigned to each group. The correction was noted in the operative report and was considered to be the desired correction target. The surgical correction was calculated by comparing preoperative and immediate postoperative mMPTA measurements. The surgical accuracy, where a value close to 0 represented optimal accuracy, was defined as the absolute value of the difference between the correction target set by the surgeon and the surgical correction achieved. The median accuracy between the 2 groups was compared by a Mann-Whitney U test (significance level at 5%). The number of patients deviating from the target by>3° was analyzed with a Fisher exact test (significance level at 5%). Pre- and postoperative comparisons of the HKAA measurements could not be used because the measurement was not performed postoperatively for the CAS group. RESULTS: The median surgical accuracy on the mMPTA was 1.4° (0-4.1) for the HT group versus 1.9° (0.2-6.7) for the CAS group (p=0.85). Sixteen procedures (76%) were performed with an accuracy of<3° in the HT group versus 15 in the CAS group (68%) (p=0.73). DISCUSSION-CONCLUSION: The working hypothesis was confirmed: no differences were found between the HT and CAS groups regarding the surgical accuracy in achieving the corrections set in this series. We therefore demonstrated that HT was a highly accessible, simple and reliable technique for achieving the planned target. It can be used widely. LEVEL OF EVIDENCE: III; comparative retrospective series.

Interimplant femoral fractures.

The number of hip or knee arthroplasties, and internal fixations of the proximal and distal femur, is increasing in proportion to the growing and ageing population, whose life expectancy is lengthening. Thus, fractures of the femur between proximal and distal implants, although rare, are becoming more frequent. Women over the age of 70, with fragile bones and whose ends of the two implants are close to each other ("kissing implants") are particularly vulnerable to them. Reliable and reproducible fracture classifications exist when it comes to 2 prostheses, but they are less well established in the presence of one, or even two, non-prosthetic implants. Their treatment is difficult and must consider the possibility of fracture consolidation while ensuring or restoring the stability and role of the implants. Whether it is the main element of treatment or a complement to prosthesis revision, locked plating forms the basis of the treatment but it must be rigorous, considering that failures are mainly the result of technical errors. Other more invasive treatments (total femoral arthroplasty, cortical sleeves) are offered more rarely if consolidation appears compromised.

Accuracy of the correction obtained after tibial valgus osteotomy. Comparison of the use of the Hernigou table and the so-called classical method.

INTRODUCTION: Medial valgus-producing tibial osteotomy (MVTO) is classically used to treat early medial femorotibial osteoarthritis. Long-term results depend on the mechanical femorotibial angle (HKA) obtained at the end of the procedure. A correction goal between 3 and 6° valgus is commonly accepted. Several planning methods are described to achieve this goal, but none is superior to the other. OBJECTIVE: The main objective was to compare the accuracy of the correction obtained using either the Hernigou table (HT) or a so-called conventional method (CM) for which 1° of correction corresponds to 1° of osteotomy opening. The secondary objective was to analyze the variations observed in the sagittal plane on the tibial slope and on the patellar height. The working hypothesis was that the HT allowed a more accurate correction and that the tibial slope and patellar height were modified in both groups. MATERIAL AND METHOD: In this monocentric and retrospective study, two senior surgeons operated on 39 knees (18 in the CM group, 21 in the HT group) between January 1, 2009 and December 31, 2014. The operator was unique for each group and expert in the technique used. The correction objective chosen for each patient, and written in the operative report, was considered as the one to be achieved. The surgical correction was the difference between the pre-operative and immediate post-operative data (< 5 J) for the mechanical tibial angle (MTA) and the hip-knee-ankle (HKA) angle. Surgical accuracy, where a value close to 0 is optimal, was the absolute value of the difference between the surgical correction performed and the goal set by the surgeon. RESULTS: The median surgical accuracy on the MTA was 3.5° [0.2-7.4] versus 1.4° [0-4.1] in the CM and HT groups, respectively (p = 0.006). In multivariate analysis, with the same objective, the CM had a significantly lower accuracy of 1.9° ± 0.8 (p = 0.02). For HKA, the median accuracy was 3.1° [0.3-7.3] versus 0.8° [0-5] in the CM and HT groups, respectively (p = 0.006). Five (5/18, 28%) and 16 (16/21, 76%) knees were within 3° of the target in the CM and HT groups, respectively (p = 0.004). The median tibial slope increased in both groups. This increase was significantly greater in the CM group compared with the HT group, with 5.5° [- 0.3-13] versus 0.5 [- 5.2-5.6], respectively (p < 0.001). The median Caton-Deschamps index decreased (patella lowered) in both groups after surgery, by - 0.21 [- 1.03; - 0.05] and - 0.14 [- 0.4-0.16], but without significant difference (p = 0.19). In univariate analysis, changes in tibial slope and patellar height were not significantly related to frontal surgical correction performed according to ΔMTA (R2 = 0.07; p = 0.055) and (R2 = - 0.02; p = 0.54) respectively. DISCUSSION: The correction set by the surgeons was achieved with greater accuracy and more frequently in the HT group, confirming the working hypothesis. The HT is therefore recommended as a simple way of achieving the set objective; the tibial slope and patellar height were modified unaffected by the frontal correction performed.

Biomechanical effects of stitches on the intra-articular mid-substance of quadruple hamstring-tendon grafts for anterior cruciate ligament reconstruction - a pilot comparative cadaveric study.

BACKGROUND: There is little data in the literature regarding the preparation methods of the intra-articular portion of quadruple hamstring-tendon grafts for anterior cruciate ligament (ACL) reconstruction. The aim of this study was to compare the biomechanical properties of a sutured transplant to that of a non-sutured transplant. The hypothesis was that adding stitches to the intra-articular portion of the graft increased its resistance. METHOD: A comparative cadaveric study was carried out on five pairs of knees. The average age of the cadavers was 68 years. The exclusion criterion was past knee surgery. In the Sutured Group (SG) two stitches were made on the grafts. No stitches were made on the grafts of the Non-sutured Group (NSG). A tensile failure test was carried out using an Instron® loading machine. The maximal load to failure and stiffness were recorded and we observed the mode of failure for each graft. Statistical analysis was performed using the Wilcoxon rank sum test. Level of significance was set at p < 0.05. RESULTS: The hypothesis proposed was not confirmed; adding stitches to the intra-articular portion of the four-strand hamstring-tendon graft does not increase its biomechanical properties. The maximal load to failure was 233.5 N ± 40.6 (186.7-274.5 N) for the NSG, 19.6% higher than for the SG which was 195.2 N ± 42.9 (139.0-238.2 N). Nevertheless, the difference observed was not statistically significant (p = 0.188). The stiffness of the grafts for the NSG was 23.5 N/mm ± 5.3 (17.8-29 N/mm) and 19.7 N/mm ± 5.5 (13.2-24.7 N/mm) for the SG grafts. Overall stiffness values for the NSG were 19% higher than those of the SG; however, the results were not statistically significant (p = 0.438). The failure mode was a rupture at the fixation point except for one sample from the SG which failed at an intra-articular stitch. CONCLUSION: Whilst the initial hypothesis was not verified, nevertheless, the maximal loads to failure and stiffness were approximately 20% higher when there were no intra-articular stitches compared to the situation where stitches were added to the intra-articular portion of the graft. This was a cadaveric pilot study and, therefore, whilst we are not able to extend our results to clinical practice, the outcomes would indicate the need for further development of this and related protocols deriving from the question of whether there is weakening the graft when adding stitches to its mid-substance. These results remain to be confirmed by further research.

Influence of femoral morphology and canal fill ratio on early radiological and clinical outcomes of uncemented total hip arthroplasty using a fully coated stem.

AIMS: The diversity of femoral morphology renders femoral component sizing in total hip arthroplasty (THA) challenging. We aimed to determine whether femoral morphology and femoral component filling influence early clinical and radiological outcomes following THA using fully hydroxyapatite (HA)-coated femoral components. METHODS: We retrospectively reviewed records of 183 primary uncemented THAs. Femoral morphology, including Dorr classification, canal bone ratio (CBR), canal flare index (CFI), and canal-calcar ratio (CCR), were calculated on preoperative radiographs. The canal fill ratio (CFR) was calculated at different levels relative to the lesser trochanter (LT) using immediate postoperative radiographs: P1, 2 cm above LT; P2, at LT; P3, 2 cm below LT; and D1, 7 cm below LT. At two years, radiological femoral component osseointegration was evaluated using the Engh score, and hip function using the Postel Merle d'Aubigné (PMA) and Oxford Hip Score (OHS). RESULTS: CFR was moderately correlated with CCR at P1 (r = 0.44; p < 0.001), P2 (r = 0.53; p < 0.001), and CFI at P1 (r = - 0.56; p < 0.001). Absence of spot welds (n = 3, 2%) was associated with lower CCR (p = 0.049), greater CFI (p = 0.017), and lower CFR at P3 (p = 0.015). Migration (n = 9, 7%) was associated with lower CFR at P2 (p = 0.028) and P3 (p = 0.007). Varus malalignment (n = 7, 5%), predominantly in Dorr A femurs (p = 0.028), was associated with lower CFR at all levels (p < 0.05). Absence of spot welds was associated with lower PMA gait (p = 0.012) and migration with worse OHS (p = 0.032). CONCLUSION: This study revealed that femurs with insufficient proximal filling tend to have less favourable radiological outcomes following uncemented THA using a fully HA-coated double-tapered femoral component.Cite this article: Bone Joint Res. 2020;9(4):182-191.

Total hip arthroplasty with exclusive use of dual-mobility cup after failure of internal fixation in trochanteric fracture.

INTRODUCTION: Failure of internal fixation in trochanteric fracture (or extracapsular proximal femoral fracture: PFF) is a serious complication often requiring total hip arthroplasty (THA). THA after PPF incurs a higher risk of complications than in intracapsular fracture due to frequent impact on local anatomy, notably with risk of implant dislocation. Recent studies demonstrated a protective effect of dual-mobility (DM) cups against instability in these cases but in a population mixing failure of internal fixation in intra- and extracapsular fractures. We therefore conducted a retrospective study focusing on fixation failure in PFF: 1) to assess surgical complications and notably dislocation rate using DM cups, and 2) to analyse the characteristics of the initial fixation and assess conformity with established standards. HYPOTHESIS: DM cups exert a protective effect in PFF fixation failure at high risk of instability. MATERIALS AND METHODS: A single-centre retrospective study included 40 cases over a 10-year period: 30 women, 10 men; mean age, 77 years [range, 31-91 years]. All THAs used DM cups. Approaches were transgluteal in 24 cases, posterior in 15 and anterolateral in one. Clinical assessment comprised of: pain on visual analog scale (VAS), Harris Hip Score (HSS), and Postel Merle-d'Aubigné score (PMA). The rate of surgical complications (periprosthetic fracture, infection, non-union, dislocation) was assessed and the primary fixation quality was analysed for fracture complexity and conformity to standards. RESULTS: At a mean 54 months' follow-up [range, 24-122 months], the post-THA complications rate was 22% (9/40), although with no cases of implant dislocation. Pre- to postoperative comparison found significant improvements on VAS (7.9±1.6 versus 1.35±1.5, respectively), HHS (20±11.8 versus 78±12.3) and PMA (4.7±2.9 versus 14.6±2.1) (p<0.0001), but non-significant change in Parker-Palmer score (5.5±2 and 4.8±1.9) (p=0.4). Fracture instability rate was 77% and 85% (31 and 34/40) on the AO and Evans-Jensen classifications respectively. Analysis of primary fixation found non-conformity with reduction standards in 68% of cases (27/40): most frequently, cervical screw centering defect (58%, 23/40) and reduction defect (28%, 11/40). The non-conformity rate was 44% (4/9) in AO stable fracture and 74% (23/31) in unstable fracture. CONCLUSION: The study hypothesis was confirmed, with no dislocations in this high-risk population. This can be attributed to exclusive use of DM cups, which should be systematic in high-risk contexts. The study confirmed the importance of primary fixation quality, although a risk of failure remains, even in stable fractures. LEVEL OF EVIDENCE: IV, retrospective study.

Revision of anterior cruciate ligament reconstruction with a pedicled quadruple hamstring autograft.

INTRODUCTION: Results of iterative ACL reconstructions are lower than after primary reconstructions. Our aim was to report the results of a retrospective series of revision using pedicled quadruple hamstring autograft. The hypothesis was that the results were satisfactory and comparable to the literature. METHODS: The study period was from January 2012 to December 2014. Fourteen patients (average age 26) were included. A fascia lata graft was used 12 times for primary reconstruction. Trauma was the cause of failure 12 times. The time interval between primary reconstruction and revision was 6.2 years. Preoperative scores used were LYSHOLM, TEGNER and IKDC. Sagittal stability was measured using the KT-1000 device. X-rays and MRI were performed to confirm the diagnosis, look for preoperative osteoarthritis and evaluate the position of the bony tunnels (Bernard and Hertel). Bone tunnels were in a proper position 14 times. RESULTS: At 45-month follow-up, improvement of objective IKDC score was significant (85.7% A/B, p < 0.0002) as well as subjective IKDC score (85.5, p < 0.0004). A significant improvement was established for the LYSHOLM score (91.8, p = 0.001) using the Wilcoxon test. The average LYSHOLM score was 92% (p > 0.5), and the average TEGNER score was 5.5 (p = 0.003). The Lachman test found a hard stop in all patients. The pivot shift test was negative for 78.5% of the cases. The laxity measurement found 12 cases with less than 3 mm. One persistent distal hypoesthesia at 2-year follow-up was observed. CONCLUSION: The hypothesis was confirmed. This series differs by the cause of failure, which was essentially traumatic, and the initial predominance of a fascia lata graft. These results remain to be confirmed. LEVEL OF EVIDENCE: Retrospective case series, level IV.

Meniscus sutures by arthrotomy for a non-transfixing horizontal lesion associated with a cyst.

INTRODUCTION: Meniscal cysts are rare in Stoller grade II horizontal lesions. Several techniques are described in the literature for their management, without any real gold standard. The objective of this work was to report a series of meniscal sutures associated with cyst resection by arthrotomy. The hypothesis was that the results were satisfactory and comparable with the data in the literature regardless of the technique reported without morbidity added by arthrotomy. MATERIALS AND METHODS: This was a monocentric retrospective study on 13 patients, aged 33 on average with a grade II meniscus lesion associated with a cyst (9 lateral and 4 medial menisci). Pre-operative data available was the VAS (5.7/10) and the Lysholm score (61/100). Primary endpoints were as follows: pain (visual analogue scale), global satisfaction, Lysholm functional score, and return to sports and professional activities at a minimum of two years. Secondary endpoints were complications, possible recurrence, and/or surgical revision. Recurrences, complications, and surgical recovery were gathered. RESULTS: Patients were evaluated with an average follow-up of 32 months. All patients were satisfied or very satisfied. The VAS significantly improved (0.2/10, p < 0.05) as well as the Lysholm score (97/100, p < 0.05). All patients returned to their professional activity: 11 within two months, one within six weeks, and one in the first post-operative week (this patient being a student). Only one patient did not resume pre-operative sport level due to a femoropatellar syndrome, not linked to the meniscal surgery performed. However, only 11 patients resumed their previous sport level (84.6%). No recurrence or surgical revision occurred. DISCUSSION: The results are good and similar to the literature, confirming the working hypothesis. These results are equivalent to partial meniscectomies and arthroscopic sutures associated with a procedure on the cyst by arthroscopy or arthrotomy. The literature is in favour of a procedure on the cyst. CONCLUSION: The results confirm the effectiveness of a direct approach suture of non-transfixing meniscal lesions associated with a cyst resection with a good functional recovery, without additional morbidity. The hypothesis was confirmed.

Early mechanical complications following fixation of proximal femur fractures: From prevention to treatment.

Proximal femur fractures have significant functional repercussions in both older adults (sometimes life-threatening) and younger adults (socioeconomic). This study will review the early mechanical complications (EMC) associated with the fixation of femoral neck (FNF) and trochanteric (TF) fractures. What is the nature of these complications? They consist of incorrect fracture fixation, secondary displacement and/or fixation failure (FNF: 3-10%; TF: 5-7%), and more rarely, secondary fractures distal to the implant. What are the risk factors and how can they be controlled? They are related to the patient (osteoporosis), to the type of fracture (FNF: posterior comminution, magnitude of displacement, vertical fracture line, fracture of calcar/TF: comminution of calcar, lesser trochanter fracture, metaphyseal comminution, lateral cortex fracture, greater trochanter comminution), to the chosen treatment (FNF: triple screw fixation or screw-plate are preferable/TF: all implants suitable for simple fractures, cervicomedullary implants for complex fractures), and to the surgical technique (quality of reduction, implant positioning). How should they be treated? Early revision of internal fixation can be difficult and increases the infection risk. Inter- or subtrochanteric valgus osteotomy leads to satisfactory results but is difficult to carry out. Secondary arthroplasty, which is the preferred option in older adults, leads to good outcomes but is technically more difficult, and has a higher complication rate in EMC of trochanteric fractures. LEVEL OF EVIDENCE: V.

Effect of saw blade geometry on crack initiation and propagation on the lateral cortical hinge for HTO: Finite element analysis.

INTRODUCTION: The hinge plays a primary role in the hold and healing of a high tibial osteotomy (HTO). Weakening of the hinge is a risk factor for failure. The aim of our study was to determine whether the geometry of the saw blade's cutting edge impacts crack initiation or propagation on the hinge. HYPOTHESIS: A certain cutting edge geometry exists that will reduce this risk. MATERIALS AND METHODS: A finite element model with transverse isotropic elastic bone properties was created. A 1.27-mm thick saw cut (full thickness in anteroposterior direction) was made leaving a 1cm lateral cortical hinge. Three different cutting edge geometries were compared: rectangular, U-shaped, V-shaped. Opening of the osteotomy was done over 1mm for 1 s by a load applied distally with the proximal portion fixed. In the first simulation, no crack was initiated at the hinge, while in the second simulation, the beginnings of a 2mm crack angled upward at 15° was added. These two simulations were used to identify whether a local stress riser was present at the hinge. This information was used to calculate the energy release rate to the hinge, which corresponds to the energy needed to initiate and propagate a crack on the hinge. RESULTS: In the first simulation (no crack initiation), a rectangular saw blade geometry resulted in the lowest local stress concentration. In the second simulation (with crack initiation), the U-shaped geometry resulted in the lowest local stress concentration. The U-shaped geometry had the lowest energy release rate, meaning that it was the least likely to initiate and propagate a crack on the lateral cortical hinge. DISCUSSION/CONCLUSION: Keeping the inherent limitations related to computer modelling in mind, our findings show that a U-shaped cutting edge is least likely to initiate or propagate a crack since it has the lowest energy release rate. This confirms our hypothesis. LEVEL OF EVIDENCE: V, expert opinion.

Clinical, functional, and isokinetic study of a prospective series of anterior cruciate ligament ligamentoplasty with pedicular hamstrings.

PURPOSE: Few studies describe the specific results of anterior cruciate ligament reconstruction with pedicled hamstring graft (HG). Our goal was to report the isokinetic, clinical, and functional outcomes over the post-operative year following pedicled hamstring ligamentoplasty. METHODS: Twenty-four patients with ACL rupture (mean age 27.4 years) were included prospectively. The technique used a four-stranded HG transplant pedicled to the tibia. The functional result (Lysholm knee score and subjective IKDC score), clinical result (KT-1000, Lachman test, joint amplitudes, objective IKDC score), and isokinetic complication occurrence were analyzed at six months and 12 months follow-up. The functional results, clinical parameters, and complications were analyzed at 30 months follow-up. The comparison of the variables with the various regressions was carried out by a Wilcoxon sign test. RESULTS: Twenty-one patients were reviewed at six, nine, 12, and 30 months. The mean Lysholm knee score was 90/100 at six months, 96/100 at one year, and 95/100 at 30 months. The mean subjective IKDC score was 77/100 and 89/100 at six and 12 months, and 91/100 at 30 months. The mean difference in laxity compared with the healthy knee was 1.4 mm at six months, 1.9 mm at 12 months, and 2 mm at 30 months. The objective IKDC score was A or B for all patients at 12 and 30 months. The average quadriceps strength deficit decreased from 27 to 16% between six and 12 months post-operative (p = 0.0091) and the average flexor deficit from 23 to 12% (p = 0.0084). No complications were identified. CONCLUSION: The abovementioned technique allows reaching functional, clinical, and isokinetic results comparable with the standard techniques while preserving the mechanical and biological interest of tibial insertion.

Total knee arthroplasty in patients with varus deformities greater than ten degrees: survival analysis at a mean ten year follow-up.

INTRODUCTION: Total knee arthoplasty (TKA) is a secure procedure with more than 90% survival at ten years. The purpose of this study was to report both clinical and radiological outcomes of TKA with a varus > 10°. The second objective was to identify risk factors for failure or bad clinical results. Our hypothesis was that results and survey are comparable to TKA with lesser deformities. METHODS: Eighty-two TKA (69 patients) between January 2004 and December 2008 with a varus > 10° were reviewed retrospectively. The endpoints were clinical (range of motion, IKS knee score, Oxford, and SF-12) and radiological (HKA post-operative and the existence of radiolucent lines or loosening at last follow-up). RESULTS: Sixty-three TKA (55 patients) were assessed with a mean follow-up of 10.9 years. The global IKS score significantly increased (p = 0.04). Seven TKA needed a revision: two for sepsis, four for aseptic loosening, and one for polyethylene wear, with an overall survival of 91.6% at ten years. For aseptic loosening, the survival rate was 94.7% at ten years. Risk factors for failure were age (p = 0.001), weight (p = 0.04), and a post-operative HKA lesser than 175° (p = 0.05) for aseptic loosening. DISCUSSION: The hypothesis was confirmed: the results showed a significant improvement of function and quality of life with a survival rate comparable to those found in the literature for greater varus but also inferior to 10°. Three risk factors have been identified suggesting increased surveillance in these cases. CONCLUSION: The results of this survey confirm the work hypothesis. Total knee arthroplasty in patients with important axial deformities is a confirmed, reliable, patient-friendly and predictable good outcome procedure.

Mechanical advantage of preserving the hamstring tibial insertion for anterior cruciate ligament reconstruction - A cadaver study.

INTRODUCTION: The best fixation method for an anterior cruciate ligament (ACL) graft is debated. The tibial fixation of tendon grafts is the principal weak point for mechanical and anatomical reasons. Preserving the tibial insertion for hamstring grafts during ACL reconstruction make provide a mechanical benefit. The aim of this study was to compare the strength at the tibial tunnel of a hamstring graft with intact tibial insertion without a screw, to that of a graft with intact tibial insertion and screw fixation, and to that of a free graft with screw fixation. We hypothesized that preserving the graft's tibial insertion increases the maximum resistance of the tibial fixation relative to a free graft. MATERIALS AND METHODS: Five pairs of knees (10 specimens) from frozen human donors were used. The tendons of the semitendinosus and gracilis were prepared as a four-strand graft while preserving their tibial insertion. The graft was passed through the tibial tunnel using standard instrumentation and the usual landmarks. Three conditions were tested: group 1 - graft with intact tibial insertion without interference screw; group 2 - graft with intact tibial insertion and interference screw; group 3 - knees from group 1 in which the tendons were detached (free graft) after the first test and fixed with an interference screw in the tibial tunnel. The screw diameter was chosen based on the graft diameter. The specimens were tested in traction using a materials testing system (Instron® 8500 PLUS) in the axis of the tunnel. The main outcome measure was the maximum load at failure (N). The secondary outcome measure was the stiffness. The groups were compared using the Friedman test and the Nemenyi post-hoc test with a 5% threshold. RESULTS: The load at failure was 33% higher in group 1 than group 3 (89.2N vs. 67.2N, p>0.05). The load at failure of group 2 was 25% higher than group 1 (111.2N vs. 89.2N, p>0.05) and 65% higher than group 3 (111.2N vs. 67.2N p=0.005). There were no differences in stiffness between groups 1 and 2 (p=1). DISCUSSION: Our hypothesis was confirmed-preserving the tibial insertion of hamstring tendons intended for ACL reconstruction increases the maximum load to failure at the tibial tunnel. Under these experimental conditions it seems that adding a screw increases the pullout strength of the graft by +25% in absolute terms; however this difference was not statistically significant. LEVEL OF EVIDENCE: III, controlled laboratory study.