Previous research has shown that tunnel placement is critical in ACL reconstruction. The ultimate position of both the femoral and tibial tunnel determines knee kinematics and overall function of the knee post surgery. As with all techniques there is a definite learning curve for the arthroscopic technique. However, the effect of the learning curve on tunnel placement has been studied sparsely. The purpose of this project therefore is to investigate the effect of the learning curve on tunnel placement. Postoperative radiographs of the first 200 anterior cruciate reconstructions with bone-tendon-bone patella tendon of a single orthopaedic surgeon performed during the first four years of independent practice were analysed for tunnel placement. Radiographs were digitalised and imported into a CAD program. Tunnel placement both femoral and tibial antero-posterior and sagittal was assessed using Sommer's criteria. A rating scale was developed to assess overall placement. A total of 100 points indicated perfect placement. A maximum of 30 points each were allocated for sagittal femoral and tibial placement and a maximum of 20 points each were allocated for coronal placement. Tunnel placement scores improved from 66 for the first 25 procedures to 87 for the last 25 procedures. Sagittal femoral placement (zone 1–4 with zone 1 being the preferred zone of placement) improved from an average of 1.44 to 1.08. Sagittal tibial placement (45% from anterior border of tibia) did not change significantly and remained between 42.82 t0 44.76%. Coronal femoral placement (between 10:00–11:00 o'clock for the right knee and 1:00–2:00 for the left knee) ranged from 10.45–11.15 and 12:45-1:15 o'clock respectively. This finding may be related to the transtibial tibial technique used to place the femoral tunnel. Coronal tibial placement (45% from medial tibial border) ranged from 45-46.58%. Correct placement of the femoral and tibial bone tunnels is important for a successful reconstruction of the anterior cruciate ligament (ACL). This study demonstrated a definitive learning curve and steady improvement of tunnel placement. Whilst there was no significant improvement in sagittal placement, overall placement improved significantly

There is increasing interest in the placement of the femoral and tibial tunnels for anterior cruciate ligament (ACL) reconstruction, with a trend towards a more anatomically accurate reconstruction. Non-anatomical reconstruction of the ACL has been suggested to be one of the major causes of osteoarthritis in the knee following ACL rupture. Knee surgeons from an international community were invited to demonstrate their method for arthroscopic ACL tunnel placement in an ACL deficient cadaveric knee. These positions were recorded with image intensification and compared with the native ACL insertion sites, which had previously been recorded with image intensification, before the ACL had been resected. Some clear trends were observed; the use of three tunnel placement techniques (anatomic ridges, ‘ruler method’ and use of image intensification) was associated with most accurate position of the femoral tunnel in the centre of the native ACL femoral insertion site. The choice of arthroscopy portals also affected tunnel placement. There is considerable variation in ACL reconstruction tunnel placement amongst experienced knee surgeons. This study provides useful information as to which tunnel placement methods are associated with the most anatomically accurate ACL reconstruction

Introduction. Anatomical reconstruction of the Anterior Cruciate Ligament (ACL) reconstruction has been shown to improve patient outcome. The posterior border of the anterior horn of the lateral meniscus (AHLM) is an easily identifiable landmark on MRI and arthroscopy, which could help plan tibial tunnel position in the sagittal plane and provide anatomical graft position intra-operatively. Method. Our method for anatomical tibial tunnel placement is to establish the relation of the posterior border of AHLM to the centre of the ACL footprint on a pre-operative sagittal MRI. Based on this relationship studied on preoperative MRI scan, posterior border of AHLM is used as an intra- operative arthroscopic landmark for anatomic tibial tunnel placement during ACL reconstruction. This relationship has been studied on 100 MRI scans where there was no ACL or LM injury (Bone and Joint Journal 2013 vol 95-B, SUPP 19). The aim of the study is to validate our method for anatomical tibial tunnel placement. Results. 25 patients with ACLR where there were both pre and post op MRI scan with good quality images of AHLM and tibial tunnel opening were included in this study. The preoperative relationship between posterior border of AHLM and centre of ACL footprint was compared with that between the posterior border of AHLM and centre of tibial tunnel on postop MRI scans. The measurements were done by two observers on two different occasions to establish intra and inter observer correlation. Discussion and Conclusion. There was significant correlation between pre-op (0.4mm) and post-op (0.4mm) distances between the AHLM and the centre of the ACL footprint/graft. There was significant inter-observer correlation (paired T-test =0.89, p<0.05) in pre- and post-op measurements. No significant difference was found in the difference between the means in pre-op and post-op MRI scans between observers (p=0.79). These results suggest that the AHLM is a reliable and valid intra-operative marker for anatomic ACL tibial tunnel placement

Introduction. Anatomical reconstruction of the Anterior Cruciate Ligament (ACL) reconstruction has been shown to be desirable and improve patient outcome. The posterior border of the anterior horn of the lateral meniscus (AHLM) is an easily identifiable arthroscopic landmark, which could guide anatomic tibial tunnel position in the sagital plane. The aim of the study was to establish the relationship between the posterior border of AHLM and the centre of the ACL foot print to facilitate anatomical tibial tunnel placement. Materials/Methods. We analysed 100 knee MRI scans where there was no ACL or lateral meniscal injury. We measured the distance between the posterior border of the AHLM and the midpoint of the tibial ACL footprint in the sagital plane. The measurements were repeated 2 weeks later for intra-observer reliability. Results. The mean distance between the posterior border of the AHLM and the ACL midpoint was −0.1mm (i.e. 0.1mm posterior to the ACL midpoint). The range was 5mm to −4.6mm. The median value was 0.00mm. 95% confidence interval was from 0.3 mm to −0.5 mm. A normal, parametric distribution was observed and Intra-observer variability showed significant correlation (p=0.01) using Pearsons Correlation test. Conclusion. Using the posterior border of the AHLM is a reliable, reproducible and anatomic marker for the midpoint of the ACL footprint in the majority of cases. It can be used intra-operatively as a guide for tibial tunnel and graft placement allowing anatomical reconstruction. There will inevitably be some anatomical variation. Pre-operative MRI assessment of the relationship between AHLM and ACL footprint is advised to improve surgical planning

Background

Recent publications have supported the anatomic placement of anterior cruciate grafts to optimise knee function. However, anatomic placement using the anteromedial portal has been shown to have a higher failure rate than traditional graft placement using the transtibial method. This is possibly due to it being more technically difficult and to the short femoral tunnel compromising fixation methods. It also requires the knee to be in hyper flexion. This position is not feasible during with a tourniquet in situ on the heavily muscled thighs of some athletes.

Hypothesis: That navigation can be used to place the femoral tunnel in the anatomic position via a more medial transtibial tunnel.

ACL reconstruction is successful in restoring sagittal stability of the knee but has been less consistent in restoring rotational stability. Increasing coronal graft obliquity improves rotational constraint of the knee in cadaveric biomechanical models. The purpose of this study was to determine whether there is a correlation between coronal graft alignment and tibial rotation during straight line activities.

Seventy-four patients who had undergone ACL reconstruction using a transtibial technique were evaluated. They came from three distinct time periods during which the operating surgeon had deliberately changed the position of the femoral tunnel to progressively achieve a more oblique graft alignment in the coronal plane. Post-operative radiographs were analyzed for the coronal graft orientation and femoral and tibial tunnel positions. Tibial rotation was measured during level walking (n=74) and single-limb landing (n=42) tasks using a motion analysis system. Radiographic measurements of graft and tunnel orientation were correlated with rotational excursion of the knee recorded during these tasks. No correlations were found between knee rotational excursion and either the coronal tibial tunnel angle or the coronal graft angle during level walking. For the single-limb landing task, a significant negative correlation was observed between the coronal angle of the tibial tunnel and rotational excursion (r=−0.3, p=0.05) i.e. increasing tunnel obliquity was associated with decreasing rotational excursion. For the coronal angle of the ACL graft, the correlation was also negative, but was not significant (r=−0.24, p=0.12).

Increases in graft obliquity in the coronal plane were associated with reduced tibial rotational excursions during single limb landing. These findings support the notion that ACL graft orientation may play a role in rotational kinematics of the ACL reconstructed knee, particularly during higher impact activities.

Anatomic all-inside ACL reconstruction using TransLateral technique is a relatively new technique that reduces surgical invasion and pain leading to early recovery. We evaluated clinical outcomes of patients undergoing primary anatomic all-inside ACL reconstruction using TransLateral technique. Retrospective case-series evaluating patients undergoing surgery from June 2013 – December 2017. Patients were followed up clinically and using PROMS including EQ-5D, KOOS, IKDC and Tegner scores. Paired two-tailed student t-tests were used to assess clinical significance. 138 patients were included (115 males, 23 females). Mean age was 30 years (range 16.0 – 60.2). Graft choice included isolated semitendinosus (n=115) or both semitendinosus and gracilis (n=26). Mean graft length and diameter were 62.1mm and 8.7mm. Sixteen cases (11.3%) returned to theatre; MUA for arthrofibrosis (n=4), infection (n=2), haemarthrosis (n=1) and metalwork failure (n=1). Incidence of graft re-rupture was 5.7% (n=8); 7 cases were in the mid-bundle femoral tunnel placement. 52.5% (n=74) had complete peri-operative PROMS scores. Mean peri-operative EQ-5D VAS scores were 69.8 and 78.2 (p=0.02). Mean peri-operative KOOS scores for all domains demonstrated significant improvements (p<0.001). Mean peri-operative IKDC scores were 46.1 and 72.5 (p<0.05) and peri-operative Tegner activity scores were 3.3 and 5.3 (p<0.001). Anatomic all-inside ACL reconstruction using TransLateral technique demonstrates favourable clinical and biomechanical advantages including independent anatomic femoral tunnel placement, bone preservation and use of single tendon graft. Patients report significant improvements in pain, functional outcome, quality of life and return to sports. Mid-bundle femoral tunnel placement has been abandoned due to higher failure rate

There has been a lot of focus on the value of anatomic tunnel placement in ACL reconstruction, and the relative merits of single and double bundle grafts. Multiple cadaveric and animal studies have compared the effects of tunnel placement and graft type on knee biomechanics. 45 patients who underwent ACL reconstruction were included into our study. Femoral tunnel position was analysed by two independent doctors using the radiographic quadrant method as described by Bernard et al., and the mean values calculated. Forty-one of these patients completed a KOOS questionnaire. The mean ratio ‘a’ was 26.57% and mean ratio ‘b’ was 30.04% as compared to 24.8% (+/− 2.2%) and 28.5% (+/− 2.5%) respectively quoted by Bernard et.al, as the ideal tunnel position. Only twenty-three of these femoral tunnels were in the anatomic range. Analysis of forty-one KOOS surveys (23 anatomic, 18 non-anatomic) revealed no significant difference in total score or subscales between the anatomic and non-anatomic groups (p= >0.05). Our study suggests that the ideal tunnel position, as described by Bernard et.al. may not be ideal and fixed

Evaluate precisely and reproducibly tridimensional positioning of bone tunnels in anterior cruciate ligament reconstructions (ACL). To propose biplanar stereoradiographic imaging as a new reference in tridimensional evaluation of ACL reconstruction (ACLR). Comparing knee 3D models issued from EOStm low-irradiation biplanar X-Ray with those issued from computed tomography (CT-Scan) high definition images will allow a bone morphological description of a previously unseen precision. We carried out the transfer of 3D models from EOStm X-Ray images obtained from 10 patients in the same reference frame with models issued from CT-Scan. Two evaluators reconstructed both pre-operative and post-operative knees, using two different stereoradiographic projections, for a total of 144 knee 3D models from EOStm. A surface analysis by distance mapping allowed us to know the differences or errors between the homologous points of the EOStm and CT reconstructions, the latter being our “bronze-standard”. At the femur, we obtained a mean (95% confidence level) error of 1.5 mm (1.3–1.6) between the EOStm models compared to the Arthro-CT segmentations when using AP-LAT incidences, compared to 1 mm (1.0 – 1.1) with oblique projections. For the tunnels placement analysis, the total radius difference between EOStm and Arthro-CT's femoral tunnel apertures was 0.8 mm (0.4–1.2) in AP-LAT and 0.6 mm (0.0–1.2) in oblique views. These femoral apertures positioning on EOStm models were within 4.3 mm (3.0–5.7) of their homologues on CT-Scan models, 4.6 mm (3.5–5.6) with the oblique views. Furthermore, 9.3o (7.2–11.4) of difference in direction between femoral tunnels from EOStm models and CT reconstructions is obtained with AP-LAT projections, 8.3o (6.6–10) with obliques views. Measures of these parameters were also performed at the tibia. According to the intra and inter-reproducibility analysis of our knee 3D models, EOStm biplanar X-Ray images prove to be fast, efficient and precise in the design of ACLR 3D models with respect to CT-Scan. Our results also propose the recourse of oblique stereoradiographic projections for the realization of knee 3D models. These models will be subjects of further analysis and will allow us eventually to propose a new frame of reference guiding the positioning of the tunnels in the ACLR

Purpose of Study:. Various techniques have been described and are still used for treating recurrent dislocation of the patella when conservative measures fail. Among them are distal, proximal and combined realignment techniques and lateral releases. Since being shown proof of the biomechanical importance of the medial patellofemoral ligament (MPFL) in patellofemoral instability, the reconstruction of the MPFL has gained in popularity. The objective of this paper is to present a case series with preliminary clinical results using the gracilis tendon to reconstruct the MPFL. Method:. Between 01/07 and 03/11 23 knees in 21 patients underwent reconstruction of the MPFL.4 of these patients had had previous surgery. Preoperatively the Caton Deschamps ratio using plain x-rays was worked out and the TT/TG distance was measured using CT scanning. Using these measurements as a guideline, 7 cases underwent a tibial tubercle transfer as an additional procedure. In 6 of the cases an additional cartilage procedure was required. The technique was simplified using intra-operative x-rays to achieve anatomical tunnel placement. Results:. The Tegner Activity Score was used to evaluate the patients preoperatively and at a minimum of 6 months postoperatively. The scores improved on average from 3,6 to 7,4. One patient had an extensor lag of 10 degrees at 3 months. This had normalised by 6 months. One patient had recurrence of her instability and required a revision MPFL reconstruction using an allograft. One patient had recurrent episodes of patella subluxation but no overt dislocation. Conclusion:. This case series gave good functional results using the Tegner Activity score. The procedure of MPFL reconstruction was effective in stabilising the patellae and in improving the symptoms of patellofemoral instability

Over the last two decades, anatomic anterior cruciate ligament (ACL) reconstructions have gained popularity, while the use of extraarticular reconstructions has decreased. However, the biomechanical rationale behind the lateral extraarticular sling has not been adequately studied. By understanding its effect on knee stability, it may be possible to identify specific situations in which lateral extraarticular tenodesis may be advantageous. The primary objective of this study was to quantify the ability of a lateral extraarticular sling to restore native kinematics to the ACL deficient knee, with and without combined intraarticular anatomic ACL reconstruction. Additionally, we aimed to characterise the isometry of four possible femoral tunnel positions for the lateral extraarticular sling. Eight fresh frozen hip-to-toe cadavers were used in this study. Navigated Lachman and mechanised pivot shift examinations were performed on ACL itact and deficient knees. Three reconstruction strategies were evaluated: Single bundle anatomic intraarticular ACL reconstruction, Lateral extraarticular sling, Combined intraarticular ACL reconstruction and lateral extraarticular sling. After all stability tests were completed, we quantified the isometry of four possible femoral tunnel positions for the lateral extraarticular sling using the Surgetics navigation system. A single tibial tunnel position was identified and digitised over Gerdy's tubercle. Four possible graft positions were identified on the lateral femoral condyle: the top of the lateral collateral ligament (LCL); the top of the septum; the ideal tunnel position, as defined by the navigation system's own algorithm; and the actual tunnel position used during testing, described in the literature as the intersection of the linear projections of the LCL and the septum over the lateral femoral condyle. For each of the four tunnel positions, the knee was cycled from 0 to 90® of flexion and fiber length was recorded at 30® intervals, therefore quantiying the magnitude of anisometry for each tunnel position. Stability testing: Sectioning of the ACL resulted in an increase in Lachman (15mm, p = 0.01) and mechanised pivot shift examination (6.75mm, p = 0.04) in all specimens compared with the intact knee. Anatomic intraarticular ACL reconstruction restored the Lachman (6.7mm, p = 3.76) and pivot shift (−3.5mm, p = 0.85) to the intact state. With lateral extraarticular sling alone, there was a trend towards increased anterior translation with the Lachman test (9.2mm, p = 0.50). This reconstruction restored the pivot shift to the intact state. (1.25mm, p = 0.73). Combined intraarticular and extraarticular reconstruction restored the Lachman (6.2mm, p = 2.11) and pivot shift (−3.75mm, p = 0.41) to the intact state. There was no significant difference between intraarticular alone and combined intraarticular and extraarticular reconstruction. (p = 1.88). Isometry: The ideal tunnel position calculated by the navigation system was identified over the lateral femoral condyle, beneath the mid-portion of the LCL. The anisometry for the ideal tunnel position was significantly lower (5.9mm; SD = 1.8mm; P<0.05) than the anisometry of the actual graft position (14.9mm; SD = 4mm), the top of the LCL (13.9mm; SD = 4.3mm) and the top of the septum (12mm; SD = 2.4mm). In the isolated acute ACL deficient knee, the addition of a lateral extraarticular sling to anatomic intraarticular ACL reconstruction provides little biomechanical advantage and is not routinely recommended. Isolated lateral extraarticular sling does control the pivot shift, and may be an option in the revision setting or in the lower demand patient with functional instability. Additionally, the location of the femoral tunnel traditionally used results in a significantly more anisometric graft than the navigation's system mathematical ideal location. However, the location of this ideal tunnel placement lies beneath mid-portion of the fibers of the LCL, which would not be clinically feasible