Global varus malalignment increase from double-leg to single-leg stance due to intra-articular changes.

PURPOSE: Preoperatively planned correction for tibial osteotomy surgery is usually based on weightbearing long-leg Xrays, while the surgery is performed in a supine non-weightbearing position. The purpose of this study was to assess the differences in lower limb alignment in three different weightbearing conditions: supine position, double-leg (DL) stance and single-sleg (SL) stance prior to performing a medial opening wedge high tibial osteotomy (MOWHTO) for varus malalignment. The hypothesis of this study was that progressive limb-loading would lead to an increased preoperative varus deformity. MATERIAL AND METHODS: This retrospective study included 89 patients (96 knees) with isolated medial knee osteoarthritis (Ahlbäck grade I or II) and significant metaphyseal tibial vara (> 6°). The differences between supine position, DL stance and SL stance were analysed for the hip-knee-ankle angle (HKA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), weight-bearing line ratio (WBL) and joint line convergence angle (JLCA). RESULTS: From a supine position to DL stance, the HKA angle slightly increased from 175.5° ± 1.1° to 176.3° ± 1.1° and JLCA changed from 2.0° ± 0.3° to 1.8° ± 0.3° without a statistically significant difference. From DL to SL stances, the HKA angle decreased from 176.3° ± 1.1° to 174.4° ± 1.1° (p < 0.05) and the JLCA increased from 1.8° ± 0.3° to 2.6° ± 0.3° (p < 0.05). A significant correlation was found between ΔHKA and ΔJLCA between the DL and the SL stances (R2 = 0.46; p = 0.01). CONCLUSION: Varus malalignment increases with weight-bearing loading from double-leg to single-leg stances with an associated JLCA increase. Thus, single-leg stance radiographs may be useful to correct preoperative planning considering patient-specific changes in JLCA. LEVEL OF CLINICAL EVIDENCE: III, retrospective comparative study.

Osteochondral repair combining therapeutics implant with mesenchymal stem cells spheroids.

Functional articular cartilage regeneration remains challenging, and it is essential to restore focal osteochondral defects and prevent secondary osteoarthritis. Combining autologous stem cells with therapeutic medical device, we developed a bi-compartmented implant that could promote both articular cartilage and subchondral bone regeneration. The first compartment based on therapeutic collagen associated with bone morphogenetic protein 2, provides structural support and promotes subchondral bone regeneration. The second compartment contains bone marrow-derived mesenchymal stem cell spheroids to support the regeneration of the articular cartilage. Six-month post-implantation, the regenerated articular cartilage surface was 3 times larger than that of untreated animals, and the regeneration of the osteochondral tissue occurred during the formation of hyaline-like cartilage. Our results demonstrate the positive impact of this combined advanced therapy medicinal product, meeting the needs of promising osteochondral regeneration in critical size articular defects in a large animal model combining not only therapeutic implant but also stem cells.

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.

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.

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.

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.

Noninvasive navigated assessment of the lower limb axis prior to knee arthroplasty: a feasibility study.

The purpose of the study was to assess accuracy and repeatability of a noninvasive navigated (NIN) measurement of the lower limb axes by comparison with the conventional, invasive navigated (IN) technique. The tested hypothesis was that NIN measure will significantly differ from IN measure when performed on a supine patient under general anesthesia just prior to knee arthroplasty. The accuracy study involved 20 cases. The following measures were performed with both systems: maximal extension angle, coronal mechanical femoro-tibial angle at the previously assessed maximal extension angle, coronal mechanical femoro-tibial angle at 30° of knee flexion. NIN and IN measures were compared with the appropriate statistical tests. The repeatability study involved 14 cases. The same measures were performed with the NIN system twice by two independent observers. The intra- and inter-observer variability was assessed by the calculation of the intra-class correlation coefficient. After correction for the systematic biases, the differences between the two systems were not significant. A good correlation, a good coherence and an excellent agreement between NIN and IN measures of maximal extension angle and coronal femoro-tibial mechanical angle at maximal extension. But measures at 30° of flexion were inconsistent. The NIN system can be considered as an accurate and precise tool for the assessment of the knee extension angle and the coronal deformation at maximal extension prior to knee arthroplasty. But this system is less accurate and less repeatable when measuring coronal femoro-tibial mechanical angle at 30° of flexion and should not be used for this purpose.

Management of periprosthetic femoral fractures following total knee arthroplasties using locking plates or intramedullary nailing. Comparative study of 567 cases.

INTRODUCTION: Proximal femur fractures in elderly patients pose a common problem that requires surgical management. The main objective of this study was to compare the results of treatment by locked plate (LP) and by anterograde (AIN) or retrograde (RIN) intramedullary nailing. The secondary objective was to analyze the complications related to each group. The hypothesis of this study was that the radiological and clinical results of each group were comparable. MATERIALS AND METHODS: The data of 438 patients from 8 centers were studied retrospectively with 365 LP and 69 cases of intramedullary nailing (49 AIN and 20 RIN). The groups were comparable in terms of mean age (75±2years), mean preoperative Parker score (5.3±0.5) and mean KOOS score (74±2). Most patients lived at home before their fracture [n=375 (86%)]. At follow-up, the joint range of motion, the KOOS and Parker scores, living premises, the time required to regain full weight-bearing, the time required for consolidation as well as the reduction alignment: frontal, sagittal, horizontal. RESULTS: The average follow-up was: 79±2weeks (65 to 82). The functional and radiological results were comparable, although nailing allowed a faster return to weight-bearing (1±2weeks for nailing versus 7±2weeks for LP, p=0.048) and a better postoperative Parker score (5.5±0.5 for nailing versus 4.7±0.2 for LP, p=0.045). Rotational malalignment in femoral nailing was often in the direction of internal rotation, compared to the LP (p=0.045). Complications were comparable with the exception of mortality, which was more frequent for LP [22.5% in the LP group versus 13% in the nailing group (p=0.045)]. Complications were categorized as: mechanical complications 6.8% of LP, 5.7% of nailing (p>0.05), infections [11% of LP, 5.8% of nailing (p>0.05)], surgical revisions [2% of LP, 10% of nailing (p>0.05)]. DISCUSSION AND CONCLUSION: The hypothesis was refuted. These results show that nailing conferred a faster recovery of weight-bearing, a better Parker score, and is associated with a lower mortality rate. The morbidity rate is comparable between the two techniques. Indeed, when the indication for osteosynthesis by LP or by nailing is made, and both choices are technically justifiable, it would be prudent to favor the technique, which carries the least risk, which in this case is nailing. This conclusion must, however, be taken in to consideration with regard to the reduced number of nailing. A larger series of nailing, particularly retrograde, would be necessary to be able to confirm this last difference between the 2 groups. LEVEL OF EVIDENCE: IV; comparative retrospective study.

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.

Rehabilitation protocol after suturing the medial meniscus of a stable knee, a retrospective series of the Francophone Arthroscopy Society.

INTRODUCTION: Surgical meniscal lesions are common and 80% of cases involve the medial meniscus of a stable knee. There is a lack of consensus regarding postoperative rehabilitation protocols and a wide variation between restrictive and accelerated rehabilitation protocols exists. The main objective of this study was to report the functional results and the failure rate of the various rehabilitation protocols of the retrospective series of the French Society of Arthroscopy (SFA) after suturing the medial meniscus of a stable knee, considering whether the tear is stable or unstable. HYPOTHESIS: Our hypothesis was that accelerated rehabilitation was not associated with an increased risk of failure. MATERIALS AND METHODS: This retrospective, multicenter study was conducted across 10 centers (6 private hospitals and 4 public hospitals) including all patients tested for a medial meniscus suture in a stable knee between January 1, 2005 and November 31, 2017 for a minimum follow-up of 5years. Demographic, imaging, suturing, rehabilitation protocol, and functional TEGNER and KOOS scores were collected. Failure was defined as performing a secondary meniscectomy. RESULTS: Three hundred and sixty-seven patients were analyzed with an average follow-up of 82months. Immediate weight bearing was allowed in 85% of cases, the wearing of a brace was present in almost 74% of cases and flexion was limited in 97% of cases. Inter-group comparisons found a higher suture failure rate in the group with immediate weight bearing (35.6% vs. 20%, p=0.011) and in the group with a brace (36.9% vs. 22.4%, p<0.001). There was no difference in the 90° flexion group. The TEGNER score was higher in the non-weight bearing group (6.5 vs. 5.4, p=0.028) and the KOOS QOL score was higher in the group without a brace (82.2 vs. 66.8, p=0.025). According to a multivariate analysis, immediate weight bearing (OR=3.6, [1.62; 7.98], p=0.0016) and wearing a brace (OR=2.83, [1.54; 5.02], p<0.001) were associated with a higher failure rate. In the group of stable lesions, the use of a brace (OR=3.73, [1.62; 8.56], p=0.0019) was associated with a higher failure rate. CONCLUSION: No consensus regarding rehabilitation protocols has been established to date and the results of this retrospective series of the SFA affirm the great variability of practices at a national level. Although accelerated rehabilitation protocols are presently favored, the resumption of immediate full weight bearing should be considered with caution, being associated with a higher risk of failure in this series. Deferring weight bearing for 1 month can be considered in the event of a large tear or in the event of damage to the circumferential fibers. Wearing a brace does not seem to have any influence, while limited flexion achieved a consensus. LEVEL OF EVIDENCE: IV, retrospective study.

The frequency of medial meniscal repairs in stable knees during one year of arthroscopic activity (2021-2022) - comparison with a retrospective study (prior to 2017).

INTRODUCTION: There has been a significant increase in the use of conservative treatment for meniscal lesions due to raised awareness around the need for meniscal preservation. However, sutures of the medial meniscus (MM) in stable knees remain less frequently used. The objective of this study was to, firstly, identify the MM suture rate over one year of activity; secondly, to identify and compare the distribution of MM sutures in stable, and stabilized, knees on this prospective series; and thirdly, to compare the evolution of practices with a retrospective series of more than 5 years follow-up. HYPOTHESIS: The number of MM sutures in stable knees represents a small percentage of annual arthroscopic activity. MATERIAL AND METHODS: This multicenter study was carried out in 10 reference centers participating in the 2022 symposium of the Francophone Society of Arthroscopy (Bordeaux, Caen, Lille, Lille Louvière, Lyon, Marseille, Toulouse, Saint-Étienne, Strasbourg, Versailles). This study included a prospective series on interventions performed under arthroscopy during one year of activity. The inclusion criteria were patients operated on via an arthroscopic technique and aged over 18 at the time of the operation. Demographic data, as well as the circumstances leading to the injury, were collected. A register of the lesions found was established in order to list the lesions of the MM, the lateral meniscus (LM), the anterior cruciate ligament (ACL), the associated chondral lesions; as well as the treatment performed: meniscal suture of the MM and/or LM, meniscectomy of the MM and/or LM and ligamentoplasty of the ACL. This study also included a retrospective series comprised of only MM sutures in stable knees at more than 5 years of follow-up. RESULTS: Of the 4154 patients included, 1919 patients (46.2%) underwent surgery for ACL reconstruction and 2235 for arthroscopy without associated ligament surgery. MM sutures (in stable knees and in knees with ACL reconstruction) represented 14% of the overall arthroscopic activity (583 MM sutures) versus 8.6% for LM (360 sutures). In cases of ACL surgery, there were 895 associated meniscal lesions (337 LM and 558 MM) and 66% of MM tears (371 MM sutures) were sutured. In stable knees, MM tears were weaker (212 MM sutures out of 1359 lesions, i.e. 15%). Of all the arthroscopic procedures performed over the course of a year, MM suturing in stable knees represented 5.1% of the activity. Compared to the retrospective series (n=367), the patients were older (37 years versus 28 years) and the management of ramp lesions or root tears was noted. In both series, these tears were related to sports trauma in more than 70% of cases. CONCLUSION: MM suturing in stable knees represents a small part of annual arthroscopic activity and it occurs less frequently than during ACL reconstruction surgery. LEVEL OF EVIDENCE: IV.

Medial meniscal repair in stable knees: Survival rate and risk factors for failure at a minimum of 5 years.

INTRODUCTION: The menisci play a major role in the protection of the knee against osteoarthritis. A medial meniscus (MM) tear occurring in a stable knee is more at risk of repair failure than a suture concomitant with reconstruction of the anterior cruciate ligament. HYPOTHESIS: The survival of MM sutures in stable knees depends on the type of lesion. MATERIALS AND METHODS: This retrospective study was carried out as part of the 2022 Francophone Arthroscopy Society's symposium, across 10 centers (Bordeaux-Mérignac, Caen, Lille, Lille Louvière, Lyon, Marseille, Toulouse, Saint-Étienne, Strasbourg and Versailles) including medial meniscus sutures in stable knees performed before the end of 2017 (minimum 5 years of follow-up) with a collection of demographic, imaging, suture and postoperative protocol data, and a functional evaluation using the Knee injury and Osteoarthritis Outcome score (KOOS). The aim of this study was to analyze the medial meniscus sutures in stable knees and to evaluate their survival and their risk factors for failure according to the type of lesion; failure being defined by the use of a meniscectomy. RESULTS: Three-hundred and sixty-seven MM sutures, including 122 bucket-handle tears, were included. The KOOS score was improved by the meniscal suture by an average of 22.2 points for each sub-score (p<0.05), with an improvement, which was more marked for the bucket-handle tears. The failure rate, defined by revision surgery by meniscectomy, was 33% on average (42% for bucket-handles tears, 26% for others). The probability of survival was reduced for bucket-handle tears (62% at 5 years versus 77% for the other types). For all lesions, the main risk factor identified for failure was immediate weight-bearing [OR=3.6 (1.62; 7.98), p=0.0016]. Smoking was a failure risk factor for bucket-handle tears [OR=5.76 (1.81; 18.35), p=0.003]. CONCLUSION: MM sutures in stable knees improve knee function but present a different risk of failure depending on the type of lesion treated with a higher risk of failure for bucket-handle tears with the need for caution to be applied with regards to weight-bearing and smoking. LEVEL OF EVIDENCE: IV; 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 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.

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.

Comparison of the functional outcomes after treatment of periprosthetic hip fractures with femoral stem loosening: Locking plate fixation with or without femoral stem revision.

INTRODUCTION: Periprosthetic fractures have become one of the main reasons for revision of total hip arthroplasty, with the treatment strategy guided by the Vancouver and SOFCOT classification systems. The main objective of this work was to compare the functional outcomes and mortality rate in patients who suffered a periprosthetic hip fracture with femoral stem loosening and who were treated either by internal fixation with locking plate only, or in combination with revision of the existing femoral stem with a cemented stem. The secondary objective was to compare the blood loss, procedure duration, length of hospital stay, living arrangements, time to weight bearing and major complications between these two treatment strategies. The starting hypothesis was that there is no difference in the functional outcomes between these two groups. MATERIALS AND METHODS: This was a single center, retrospective study of patients treated between 2013 and 2019. Thirty-six patients (54%) underwent femoral stem revision (FSR group) and 31 patients (46%) were treated by locking plate fixation only (ORIF group). In this population, 19 of the patients had been residing at a nursing home before the surgical treatment: 12 (33%) in the FSR group and 7 (23%) in the ORIF group (p=0.33). The mean preoperative Parker score was 7.03 (± 1.48) in the FSR group versus 5.19 (± 1.92) in the ORIF group. The functional outcomes at the final review were evaluated using the Parker score, HHS (Harris Hip score), WOMAC (Western Ontario and McMaster Arthritis Index) and Oxford score. Fracture healing was determined on radiographs centered over the hip joint with the entire femur visible on AP and lateral views. All patients were reviewed at a minimum of 1 year for clinical and radiological assessments. RESULTS: At a mean follow-up of 28 months [12-85], the Oxford score was 40.4 (± 10.6) in the FSR group versus 37.1 (± 13.5) in the ORIF group (p=0.34), WOMAC of 45.5 (± 26.9) versus 50.5 (± 32.4) (p=0.56), and HHS of 62.7 (± 25.5) versus 60.3 (± 28.6) (p=0.79). The Parker score at the final assessment was 5.14 (± 1.96) in the FSR group versus 4.64 (± 2.17) in the ORIF group (p=0.33). In the FSR group, 10 patients were at a nursing home (34%), 6 of whom were not there initially, versus 6 in the ORIF group (43%), 5 of whom were not there initially (p=0.59). The mean operating time was 152±41.4 minutes (minimum: 85; maximum: 254) in the FSR group versus 89.2 (± 44.1) minutes (minimum: 39; maximum: 280) in the ORIF group (p<0.001). Resumption of full weight bearing occurred at 6 weeks in 21 patients (58%) in the FSR group versus 14 patients (47%) in the ORIF group (p=0.023). There were 5 major complications (14%) in the FSR group versus 7 (23%) in the ORIF group (p=0.35). Among the reviewed patients, the union rate was 86% on the latest radiographs in the FSR group versus 78% in the ORIF group. DISCUSSION: There was no statistically significant difference between groups in the various functional scores, confirming our study hypothesis. Internal fixation with a locking plate appears to be an acceptable solution for treating periprosthetic hip fractures in which the femoral stem has loosened. LEVEL OF EVIDENCE: III, comparative retrospective study.

Orientation and end zone of the osteotomy cut for high tibial osteotomy: Influence on the risk of lateral hinge fracture. A finite element analysis.

INTRODUCTION: the hinge plays a fundamental role in the support and consolidation of a high tibial osteotomy. The objective of this work was to analyse the influence of the end zone of the osteotomy cut and its orientation in relation to the articular joint line (JL) on the risk of hinge fracture. HYPOTHESIS: a specific orientation and end zone of the osteotomy cut can be utilised to decrease the risk of hinge fracture. MATERIAL AND METHOD: a finite element (FE) model was used to reproduce the proximal portion of the tibia and the proximal tibiofibular joint with transverse isotropic elastic bone properties. A 1.27mm thick, complete, anteroposterior saw cut was made with a U-shaped saw blade. Five proximal and lateral tibial zones were used according to Nakamura et al corresponding to the end zones of the osteotomy cut. Three angulations of the cut relative to the JL were defined: 10°, 15°, 20°. The tests consisted of simulating 15 possible situations (3 angulations for each of the 5 end zones) on this model. These simulations made it possible to identify the existence of a local stress concentration (von Mises, in MPa) at the level of the hinge, corresponding to the main judgment criterion. RESULTS: If we consider only the end zones of the osteotomy cut, regardless of its angulation with respect to the JL, the zone which presents, on average, the lowest local stress concentration is the AM zone (40.3MPa). If we consider only the angulation of the osteotomy cut, with respect to the JL, regardless of the end zone of the cut, the angulation that locally concentrates, on average, the least stress is an angulation at 10° (147.7MPa). Finally, it is important to define the best end zone of the osteotomy cut for each angulation value in relation to the JL: for an angulation of 10°, the end zone must be in AM (38MPa), but also for an angulation of 15° (45MPa), and for an angulation of 20° (38MPa). DISCUSSION-CONCLUSION: With the inherent caveats of the experimental conditions, the hypothesis is confirmed. An end zone of the osteotomy cut exists (AM) and an orientation (10°) that induces the lowest local stress concentration and therefore the least likely to induce lateral hinge fracture. However, the orientation of the osteotomy cut is also a matter of surgical habit, especially regarding complementary osteotomy of the tibial tuberosity that some may want to avoid. Thus, it is equally important to know the best end zone associated with a given angulation of the cut in relation to the JL, which according to these results is the AM zone for each angulation. This information helps guide the operator in their surgical practices according to their habits. LEVEL OF EVIDENCE: V, expert opinion.

Comparative effectiveness of nonsurgical interventions in the treatment of patients with knee osteoarthritis: A PRISMA-compliant systematic review and network meta-analysis.

BACKGROUND: To find out, based on the available recent randomized controlled trials (RCTs), if the nonsurgical interventions commonly used for knee osteoarthritis patients are valid and quantify their efficiency. METHODS: The database of MEDLINE and EMBASE were searched for RCTs evaluating nonsurgical treatment strategies on patients with mild to moderate knee osteoarthritis. A Bayesian random-effects network meta-analysis was performed. The primary outcome was the mean change from baseline in the Western Ontario and McMaster university (WOMAC) total score at 12 months. Raw mean differences with 95% credibility intervals were calculated. Treatments were ranked by probabilities of each treatment to be the best. RESULTS: Thirteen trials assessed 7 strategies with WOMAC at 12 months: injection of platelet rich plasma (PRP), corticosteroids, mesenchymal stem cells (MSCs), hyaluronic acid, ozone, administration of nonsteroidal anti-inflammatory drugs with or without the association of physiotherapy. For treatment-specific effect size, a greater association with WOMAC decrease was found significantly for MSCs (mean difference, -28.0 [95% CrI, -32.9 to -22.4]) and PRP (mean difference, -19.9 [95% CrI, -24.1 to -15.8]). Rank probabilities among the treatments indicated that MSCs had a much higher probability (P = .91) of being the best treatment compared with other treatments, while PRP ranked as the second-best treatment (P = .89). CONCLUSION: In this systematic review and network meta-analysis, the outcomes of treatments using MSCs and PRP for the management of knee osteoarthritis were associated with long-term improvements in pain and function. More high quality RCTs would be needed to confirm the efficiency of MSCs and PRP for the treatment of patients with knee osteoarthritis.