Artificial intelligence and machine-learning analytics have gained extensive popularity in recent years due to their clinically relevant applications. A wide range of proof-of-concept studies have demonstrated the ability of these analyses to personalize risk prediction, detect implant specifics from imaging, and monitor and assess patient movement and recovery. Though these applications are exciting and could potentially influence practice, it is imperative to understand when these analyses are indicated and where the data are derived from, prior to investing resources and confidence into the results and conclusions. In this article, we review the current benefits and potential limitations of machine-learning for the orthopaedic surgeon with a specific emphasis on data quality.

Meniscal tears commonly co-occur with ACL tears, and many studies address their side, pattern, and distribution. Few studies assess the patient's short-term functional outcome concerning tear radial and circumferential distribution based on the Cooper et al. classification. Meniscal tears require primary adequate treatment to restore knee function. Our hypothesis is to preserve the meniscal rim as much as possible to maintain the load-bearing capacity of the menisci after meniscectomy. The purpose of this study is to document the location and type of meniscal tears that accompany anterior cruciate ligament (ACL) tears and their effect on patient functional outcomes following arthroscopic ACL reconstruction and meniscectomy. This prospective cross-sectional observational study was conducted at AL-BASRA Teaching Hospital in Iraq between July 2018 and January 2020 among patients with combined ipsilateral ACL injury and meniscal tears. A total of 28 active young male patients, aged 18 to 42 years, were included. All patients were subjected to our questionnaire, full history, systemic and regional examination, laboratory investigations, imaging studies, preoperative rehabilitation, and were followed by Lysholm score 6 months postoperatively. All 28 patients were males, with a mean age of 27 ± 0.14 years. The right knee was the most commonly affected in 20/28 patients (71.4%). The medial meniscus was most commonly injured in 11 patients, 7 patients had lateral meniscal tears, and 10 patients had tears in both menisci. The most common tear pattern of the medial meniscus was a bucket handle tear (36.4%), while longitudinal tears were the most frequent in the lateral meniscus (71.4%) (P-value = 0.04). The most common radial tear location was zone E-F (5/28, 17.8%), and the most common circumferential zone affected was the middle and inner third, reported in 50% of tears. Good and excellent outcomes using the Lysholm score after 6 months were obtained in 42.9% and 17.9% of patients, respectively. Better functional scores were associated with lateral meniscal tears, bucket handle tears, tears extending to a more peripheral vascular area, and if no more than one-third of the meniscus was resected (P-value = 0.002). Less favourable outcomes were reported in smokers, posterior horn tears, and when surgery was delayed more than 1 year (P-value = 0.03). We conclude that there is a negative correlation between the amount of meniscus resected and functional outcome. Delayed ACL reconstruction increases the risk of bimeniscal tears. Bucket handle tears are the most common tears, mostly in the medial meniscus, while longitudinal tears are most common in the lateral meniscus. We recommend performing early ACL reconstruction within 12 months to reduce the risk of bimeniscal injuries

The fibrocartilaginous enthesis displays a complex interface between two mechanically dissimilar tissues, namely tendon and bone. This graded transition zone consists of parallel collagen type I fibres arising from the tendon and inserting into bone across zones of fibrocartilage with aligned collagen type I and collagen type II fibres and mineralised fibrocartilage. Due the high stress concentrations arising at the interface, entheses are prone to traumatic and chronic overuse injuries such as rotator cuff and anterior cruciate ligament (ACL) tears. Treatment strategies range from surgical reattachment for complete tears and conservative treatments (physiotherapy, anti-inflammatory drugs) in chronic inflammatory conditions. Generally, the native tissue architecture is not re-established and mechanically inferior scar tissue is formed. Current interfacial tissue engineering approaches pose scaffold-associated drawbacks and limitations, such as foreign body response. Using a thermo-responsive electrospun scaffold that provides architectural signals similar to native tissues and can be removed prior to implantation, we aim to develop an ECM-rich, cell-based implant for tendon-enthesis regeneration. Alcian blue staining revealed highest sGAG deposition in cell (human adipose derived stem cells) sheets grown on random electrospun fibres and lowest sGAG deposition in collagen type I sponges. Cells did not show an equal distribution throughout the collagen type II scaffolds but tended to form localised aggregates. Thermo-responsive electrospun fibres with random and aligned fibre orientation provided an adequate three-dimensional environment for chondrogenic differentiation of multilayer hADSC-sheets shown by high ECM-production, especially high sGAG deposition. Chondrogenic cell sheets showed increased expression of SOX9, COL2A1, COL1A1, COMP and ACAN after 7 days of chondrogenic induction when compared to pellet culture. Anisotropic fibres enabled the generation of aligned chondrogenic cell sheets, shown by cell and collagen fibre alignment. Thermoresponsive electrospun fibres showed high chondro-inductivity due to their three-dimensionality and therefore pose a promising tool for the generation of scaffold-free multilayer constructs for tendon-enthesis repair within short culture periods. Aligned chondrogenic cell sheets mimic the zonal orientation of the native enthesis as the fibrocartilaginous zone exhibits high collagen alignment

Introduction. Cruciate retaining knee replacements are only implanted into patients with “healthy” ligaments. However, partial anterior cruciate ligament (ACL) tears are difficult to diagnose with conventional MRI. Variations of signal intensity within the ligament are suggestive of injury but it is not possible to confirm damage or assess the collagen alignment within the ligaments. The potential use of Magic Angle Directional Imaging (MADI) as a collagen contrast mechanism is not new, but has remained a challenge. In theory, ligament tearing or joint degeneration would decrease tissue anisotropy and reduce the magic angle effect. Spontaneous cruciate ligament rupture is relatively common in dogs. This study presents results from ten canine knees. Methods. Ethical approval was obtained to collect knees from euthanized dogs requiring a postmortem (PM). A Siemens Verio 3T MRI scanner was used to scan a sphere containing the canine knees in 9 directions to the main magnetic field (B. 0. ) with an isotropic 3D-T1-FLASH sequence. After imaging, the knees were dissected and photographed. The images were registered and aligned to compare signal intensity variations. Segmentation using a thresholding technique identified voxels containing collagen. For each collagen-rich voxel the orientation vector was computed using Szeverenyi and Bydder's method. Each orientation vector reflects the net effect of all fibers comprised within a voxel. The assembly of all unit vectors represents the fiber orientation map and was visualised in ParaView using streamlines. The Alignment Index (AI) is defined as a ratio of the fraction of orientations within 20° (solid angle) centred in that direction to the same fraction in a random (flat) case. By computing AI for a regular gridded orientation space we can visualise differences in AI on a hemisphere. AI was normalised so that AI=0 indicates isotropic collagen alignment. Increasing AI values indicate increasingly aligned structures: AI=1 indicates that all collagen fibers are orientated within the cone of 20° centred at the selected direction. Results. Dogs cranial cruciate ligament (CCL) is similar to human ACL. It's composed of an anteromedial (AM) bundle and a posterolateral (PL) bundle. Two knees were damaged with partial CCL tears, the PL bundle was intact but the AM bundle was torn. Paraview streamlines of the CCL for healthy and damaged knees differ. The healthy knee has continuous fiber tracts with no ligament disruption. In the AM bundle fibers are discontinuous and the PL bundle fibers are continuous as expected in a partially torn CCL. The AI for healthy (mean AI=0.25) and damaged CCL (mean AI= 0.075) is significantly different (p<0.01). The damaged AM bundle has a more diffuse spread of less aligned fibers compared to the more concentrated and aligned PL fiber bundle. Conclusion. This study demonstrates the first visualisation of a CCL partial tear using MADI. Combined with AI, our scanning technique offers a tool to visualise and quantify changes in collagen fiber orientation. Thus, MRI can be used to improve the diagnosis and quantification of partial ligament tears in the knee

Aim: This retrospective study was undertaken to establish the accuracy of magnetic resonance imaging (MRI) in diagnosing medial meniscal, lateral meniscal and anterior cruciate ligament (ACL) tears. Materials and methods: Sixty patients who had arthroscopic knee surgery following MRI scans were included in the study. MRI findings were then compared with the pathologies noted at subsequent arthroscopy. Results: In this study, the sensitivity of MRI in diagnosing tears was 67% (ACL), 100% (medial meniscus) and 57% (lateral meniscus) whereas the specificity was 91%(ACL), 46 %(medial meniscus) and 77 % (lateral meniscus).The positive predictive values were 29% (ACL), 68% (medial meniscus) and 57% (lateral meniscus). The negative predictive values were 98% (ACL), 100% (medial meniscus) and 76% (lateral meniscus). Conclusion: In contrast to some studies, these findings indicate a lower accuracy for MRI scanning in detecting tears of, in particular of the ACL and lateral meniscus. We suggest that where symptoms and clinical findings support one of these diagnoses and arthroscopic therapeutic intervention is contemplated, that MRI scanning is not beneficial. The additional expense and delay in management seems inappropriate given the findings we have demonstrated

Purpose of the study: The objective was to compare the results of ligamentoplasties with two commonly used grafts, hamstring and patellar tendon. This was a prospective randomized study. Material and methods: Between January 2001 and June 2004, 98 patients with an acute or chronic anterior cruciate ligament (ACL) tear with joint instability were included in this randomized study for arthroscopic repair. Patients were randomized to the patellar or hamstring arm. Clinical assessment was based on laxity, IKDC score, Lyscholm score, pain visual analog scale (VAS), midthigh thickness and isokinetic assessment at three months. Measurements were recorded preoperatively and at 1, 3, 6 weeks and 3, 6, and 12 months. Results: The two groups were comparable regarding gender, morphotype, associated lesions, and activity level. There was no difference in operative time or in recovery of complete extension. Anterior laxity was the same in the two groups. The isokinetic deficit appeared to be greater in the bone-tendon-bone group at three months. The IKDC and Lysholm scores were not significantly different at six and twelve months. Harvesting site morbidity was more pronounced in the bone-tendon-bone group. Conclusion: The two techniques provide good results. The bone-tendon-bone technique appears to cause greater harvesting site morbidity. While the isokinetic results appear to be better in the hamstring group, the measurements of laxity and recovery of stability did not show any difference

The early surgical management of the anterior cruciate ligament (ACL) tears in children remains controversial. The argument for nonoperative treatment is driven by concerns about the risk of growth arrest caused by a transphyseal procedure. On the other hand, early surgical reconstruction is favoured because of poor compliance with conservative treatment and increased risk of secondary damage due to instability. This paper reports a series of 39 very young children who had an ACL reconstruction using a transphyseal procedure with a hamstring graft. Patients were followed to skeletal maturity or for a minimum of three years. Only those patients with either a chronological age less than 14 years or with a Tanner stage of 1 and 2 of puberty were included in the study. Thirty children were Tanner 1 or 2 and nine were Tanner 3-4 but were younger than 14. The mean age at operation was 12.2 years (Range 9.5-14.2, Median 12.4). The mean follow up was 60.7 months (range 36-129, median: 51) months. Thirty four patients had attained skeletal maturity at the last follow up. The mean Lysholm score improved from 72.4 pre-operatively to 95.86 postoperatively (p<0.0001). The mean Tegner activity scale was 4.23 after injury and it improved to 7.52 after operation (p<0.0001)) which was a reasonable comparison to the pre- injury score of 8.0. One patient had a mild valgus deformity with no functional disturbance. No other growth related abnormalities including limb length discrepancy were noted. There has been one re-rupture but all others had good or excellent outcome. This is one of the largest series reporting the long term results of ACL reconstruction in very young children. Most other studies include children up to the age of 16. Based on our results we can conclude that transphyseal ACL reconstruction modified for very young patients is a safe procedure

Purpose: To analyze the causes of repeat knee arthroscopy in the same knee. Materials and methods: We reviewed 923 patients that had undergone knee arthroscopy during 2005 and assessed those that had already undergone previous arthroscopy of the same knee that year or in previous years and analyzed the causes. Results: Of the 923 patients that required knee arthroscopy 169 (18.3%) had undergone previous surgery. Four (2.3%) had undergone 3 previous arthroscopies, 27 (15.9%) two and 138 (81.6%) one. In 59.8% of cases, the symptoms that led to repeat arthroscopy were non-traumatic continuous pain. The other cases required repeat arthroscopy due to new trauma, or meniscal or anterior cruciate ligament (ACL) tears. The patients with affected menisci (104) underwent partial meniscectomy, 31% had a posterior cruciate ligament (PCL) tear and 58% had menisci remains with or without osteochondral lesions. Repeat arthroscopies of ACL tears treated by ligamentoplasties (41) were due to plasty tears in 46% of cases and adhesions in 27%. In patients that underwent 3 arthroscopies, the main diagnosis was plasty tear in 45% of the total sum of 2. nd. and 3. rd. arthroscopies. Mean time between first and second arthroscopy was 28 months and between second and third arthroscopy 12 months. The relative risk of undergoing a new arthroscopy during the same year as meniscectomy was 1.12% and as ACL ligamentoplasty 0.95%. Conclusions: Not all repeat arthroscopies are caused by previous complications. The main clinical reasons for a repeat arthroscopy can be traumatic or non-traumatic, with a greater frequency of the latter. We found that the risk of repeat arthroscopy was greater during the first year in meniscal tears than in ACL tears

The aim of this study is to assess the accuracy of clinical examination of the knee compared to MRI and Arthroscopy in diagnosing significant internal derangement. We performed a retrospective analysis on 245 patients who underwent an MRI of the knee over a two-year period. The MRI diagnoses were compared with both clinical and arthroscopic findings. There were 169 male and 76 female patients with an average age of 33 years. A history of significant trauma was seen in 98 (40%) patients. The commonest clinical diagnosis was isolated medial meniscal tear (25%). Anterior cruciate ligament (ACL) tear was diagnosed in 8% and lateral meniscal tear in 7% of cases. No definite clinical diagnosis could be reached in 32% of patients. MRI showed no significant abnormality in 103 (42%) patients. Medial meniscal tear was noted in 47 (19%), ACL tear in 20 (8%) and lateral meniscal tear in 10 (4%) of the MRI scans. 96 patients (39%) proceeded to arthroscopy after their MRI scans. The mean time from MRI scan to arthroscopy was 181 days. The MRI and arthroscopy findings were in complete agreement in 90 (94%) patients. Of the 6 patients whose MRI findings did not correlate with arthroscopy, 4 showed meniscal tears not seen at surgery and two diagnosed ACL ruptures subsequently shown to be normal at arthroscopy. Three of the 4 meniscal tears were of the inferior surface of the posterior horn of the medial meniscus and one of the inferior surface of the lateral meniscus. The films were reviewed independently by three experienced MR radiologists all of whom confidently diagnosed a tear in each case. Clinical examination alone is not satisfactory in the diagnosis of knee injuries. MRI is a highly sensitive tool for diagnosis. Injuries that are commonly missed at arthroscopy can be diagnosed easily with MRI

Aim: To assess and establish the reason for repeating knee arthroscopies. A retrospective study at Torbay General Hospital. Methods and results: The sample period was from January-2004 to July 2007 during which 695 knee arthroscopies were done, of which 71 patients (10 %) were coded as having same knee scoped again. A total of 58 out of 71 patients notes were available for review of which 12 were excluded due to coding-error and septic-arthritis. Among the 45 patients included, 67% were males and mean age was 44 years (range 17 to 70 years). The average time from listing the patient to actual scope was 20 weeks (range 0 to 54). At their first scope 24 patients required partial meniscectomies, of which 11 (45%) and 6 (25%) patients had posterior-horn and body of medial meniscal tears respectively, and 7 (29%) had tears in posterior-horn of lateral meniscus. Among the 23 who had chondral defects, 73% had changes on medial femoral condyle, 70% on patella, 52% on medial tibial condyle, 47% over lateral femoral condyle, 43% on trochlear grove, and 39% on lateral tibial condyle. Thirty-three-percent patients had anterior cruciate ligament (ACL) tears and 6% require loose bodies removal. Average time between re-scopes was 16 months (range 0 to 3.5 years). The numbers of patients requiring repeat knee arthroscopy for similar clinical problems were 16 out of 695 patients (2.3%). During repeat arthroscopies, 10/16 (62%) required procedures on meniscus, 4/16 (25%) for osteochondral lesions 2 patients had same diagnosis as ACL tears. 90% of partial meniscectomies were repeated on the posterior horn of both medial and lateral meniscus, and 20% required trimming of body of the meniscus. Conclusion: Contrary to general opinion being too many patients knees are been re-scoped, only 16/695 patients (2.3%) had their knees re-scoped for similar problem as found at first arthroscopy. 62% of these patients required partial meniscectomy mainly on the posterior-horns and 25% had chondral defects. We concluded that MR-arthrogram should be considered due to its specificity and sensitivity as detailed in literature, before performing repeated knee arthroscopy

Purpose of the study: Free patellar tendon plasty is the most common technique for repairing anterior knee laxity. Functional outcome can be compromised by invalidating knee pain. The purpose of this prospective randomized study was to compare the outcome of plasty procedures using hamstring tendon versus patellar tendon autografts. Material and methods: From May 1998 through May 2001, 100 patients presenting an isolated grade I anterior cruciate ligament (ACL) tear were included. Exclusion criteria were: history of fracture, advanced-stage laxity (grade II or greater), and contralateral ACL tear. Randomization was performed in the operative theater using the closed envelop method. Two groups of 50 patients were designated: group A: arthroscopic free bone-tendon-bone patellar autograft; group B: arthroscopic free four-strand hamstring autograft. Two metallic interference screws were used for fixation in both groups. The two groups were comparable for demographic features and clinical, radiological, and instrumental laxity variables recorded before surgery. The position of the tunnels was noted according to Aglietti and was the same in the two groups. The same rehabilitation protocol in a dedicated center was used for both groups. All patients (none lost to follow-up) were assess using the IKDC 1993 criteria with objective instrumental measurement of residual laxity. The level of significance was set at 5%. Results: There was no significant difference between the groups regarding: resumption of sports activity (level and delay), joint motion, ligament examination, the overall IKDC score, and radiological findings ate mean 40±13 months (range 13–69 months) follow-up. Pain at the harvesting site was observed in 34.78% of patients in group A at six months and in 39.5% of those in group B. Conversely, anterior pain was found in 8.5% of patients in group B at six months and 6.6% at one year (p< 0.05). This statistically significant difference disappeared at two years. Instrumental differential laxity was 0.57±1.3 mm in group A and 1.22±1.9 mm in group B (p=0.56, but with power < 80%). There were two cases of repeated traumatic tears in each group. Repeated meniscectomy was performed in one patient in group A and in three in group B (p=0.3074). Conclusion: The results at 40 months follow-up of this prospective randomized study with no patients lost to follow-up confirmed the minimal morbidity observed at the harvesting site for hamstring plasty. There was no significant difference between the transplants (patellar tendon, hamstring). Anterior pain with the patellar tendon plasty attenuated after two years. Residual laxity was greater when using the hamstring method

Aims

There is limited information on outcomes of revision ACL reconstruction (rACLR) in soccer (association football) athletes, particularly on return to sport and the rate of additional knee surgery. The purpose of this study was to report return to soccer after rACLR, and to test the hypothesis that patient sex and graft choice are associated with return to play and the likelihood of future knee surgery in soccer players undergoing rACLR.