Remnant preservation does not affect accuracy of tibial tunnel positioning in single-bundle ACL reconstruction.

PURPOSE: Remnant preservation, in anterior cruciate ligament (ACL) reconstruction, has potential biological advantages. However, graft positioning remains vital to functional outcome and the prevention of failure. The aim of this study was to investigate the accuracy and precision of tibial tunnel positioning in remnant preservation single-bundle hamstring reconstruction. METHODS: Fifty consecutive adult patients, with isolated ACL rupture, were recruited to a prospective study. Remnant preservation was performed in all cases where > 25% of the native ACL was present. Three-dimensional computer tomography was preformed 3-6 months post-operatively to assess tibial tunnel position (using a grid-based measurement). Accuracy and precision of this technique were assessed against published anatomical data in direct comparison with the group where remnant preservation could not be performed. RESULTS: Two patients withdrew following surgery. In the remaining groups (31 remnant preservation; 17 non-remnant preservation), no difference was demonstrated in tunnel position (40.4 ± 6.7% (anterior-to-posterior) and 47.4 ± 1.5% (medial-to-lateral) vs. 38.8 ± 4.9% and 46.7 ± 1.5%, respectively; n.s.), accuracy (6.1% vs. 4.8%; n.s.) or precision (3.9% vs. 2.8%; n.s.). CONCLUSIONS: Remnant preservation can be safely performed without compromising tunnel position. Therefore, the potential benefits of this technique can be utilised, in clinical practice, without sacrificing the ability to optimize tibial tunnel positioning. LEVEL OF EVIDENCE: III.

Flexible reamers create comparable anterior cruciate ligament reconstruction femoral tunnels without the hyperflexion required with rigid reamers: 3D-CT analysis of tunnel morphology in a randomised clinical trial.

PURPOSE: The hyperflexion required for femoral tunnel drilling in anterior cruciate ligament reconstruction can be challenging in patients with increased body habitus or musculature. Whilst allowing femoral tunnel creation without hyperflexion, additional benefits of flexible reamers have been proposed in terms of tunnel dimensions. The purpose of this study was to examine whether these theoretical benefits are seen in a clinical study. METHODS: Fifty adult patients (with isolated anterior cruciate ligament rupture) were randomised to reconstruction with either flexible or rigid femoral reamers. Femoral tunnel drilling was performed at 100° flexion (flexible system) or maximal hyperflexion (rigid system). Otherwise, the procedure was standardised. Femoral tunnel measurements were performed by a consultant musculoskeletal radiologist who was blinded to the method of femoral drilling. Tunnel position, length and angles (axial and coronal) were measured alongside aperture shape and exit point using three-dimensional computed tomography 3-6 months post-operatively. RESULTS: With no difference in tunnel position, tunnel length was found to increase with the use of the flexible system (37.8 ± 3.7 vs 35.0 ± 4.4 mm; p = 0.024). In addition, the exit point and fixation device were more anterior on the lateral femur using the flexible reamers (p = 0.016). No difference was seen in either tunnel angles or aperture shape. One case of incomplete posterior blow-out was seen in each of the study groups. CONCLUSIONS: This comparative study shows that flexible reamers can reproduce a desired femoral tunnel position with only small improvements of no clinical relevance. As this can be achieved without hyperflexing the knee, these systems can be used for all patients (even when hyperflexion is a challenge). LEVEL OF EVIDENCE: I.

Staged meniscal allograft transplantation as a biologic treatment of the meniscal deficient knee: A prospective case series of 26 patients with maximum 88-month follow-up.

INTRODUCTION: The meniscal deficient knee often exists within the setting of associated pathology including instability, malalignment and chondral injury. The aim of this study was to establish the role of meniscal allograft transplantation (MAT) as part of a staged approach to treatment of the previously menisectomised knee and report: (a) primary data endpoints (pre and post-operative Knee Injury and Osteoarthritis outcome scores (KOOS), Tegner scores, satisfaction scores and graft survival), and (b) secondary endpoints:(complication/reoperation rates, and meniscal extrusion measurements as determined by MRI). MATERIAL AND METHODS: This prospective study included all patients that underwent arthroscopic fresh frozen allograft MAT at our institution (2010-2017) using a soft tissue fixation technique. RESULTS: Twenty-seven MAT procedures were performed in 26 patients (16 lateral, 11 medial). Ten patients underwent ACL reconstruction, three ACI and two osteotomy in the pre-MAT phase. Seven patients underwent ACI within the post-operative phase. Post-operative mean KOOS scores improved significantly in all subscales (p < .002) as did Tegner scores (p < .05). Graft survival was 100%, satisfaction rate 92%, and mean meniscal extrusion 3.04 mm. Post operatively, three patients required meniscal repair and a single patient, partial menisectomy of graft. Two patients underwent arthroscopic arthrolysis following MAT. CONCLUSIONS: This series highlights the multifactorial profile of the meniscal deficient knee and the role of MAT as a safe and reliable technique in the staged and comprehensive biologic treatment available to minimise symptoms and maximise outcomes. LEVEL OF EVIDENCE: 4.

The Exeter Knee Infection Multi Disciplinary Team approach to managing prosthetic knee infections: A qualitative analysis.

BACKGROUND: A Knee Infection Multi-Disciplinary Team meeting was established in Exeter. This study was designed to qualitatively evaluate the impact of the MDT on those involved. MATERIALS AND METHODS: Semi-structured interviews of all members of the MDT at Exeter were undertaken and analysed using Nvivo software. Data was coded to identify common patterns and trends. RESULTS: The common themes identified were improved communication and standardisation of care. The main challenges identified were the timing of the meetings and funding. CONCLUSION: This study has used established qualitative techniques to evaluate the impact of the Exeter Knee Infection MDT.

A comparison of femoral tunnel placement in ACL reconstruction using a 70° arthroscope through the anterolateral portal versus a 30° arthroscope through the anteromedial portal: a pilot 3D-CT study.

BACKGROUND: Graft malposition is a risk factor for failure of anterior cruciate ligament reconstruction. A 70° arthroscope improves visualisation of the medial wall of the lateral femoral condyle without switching portals. We investigated whether the use of this arthroscope affected the accuracy and precision of femoral tunnel placement. METHODS: Fifty consecutive adult patients were recruited. Following one withdrawal and two exclusions, 47 patients (30 in group 1 (70° arthroscope), 17 in group 2 (30° arthroscope)) underwent three-dimensional computed tomography imaging using a grid-based system to measure tunnel position. RESULTS: No difference was found in the accuracy or precision of tunnels (mean position: group 1 = 33.3 ± 6.0% deep-shallow, 27.2 ± 5.2% high-low; group 2 = 31.7 ± 6.9% deep-shallow, 29.0 ± 6.2% high-low; not significant). A post-hoc power analysis suggests a study of 106 patients would be required. CONCLUSIONS: This pilot study suggests that tunnel position is not affected by the arthroscope used. An appropriately powered study could investigate this finding alongside other potential benefits of using a 70° arthroscope for this procedure. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02816606. Registered on 28 June 2016.

Tibial Tuberosity Transfer in Combination With Medial Patellofemoral Ligament Reconstruction: Surgical Technique.

The stability of the patellofemoral joint relies on the tenuous interplay of soft tissue and bony factors. Anatomic risk factors for instability include a shallow trochlea, an abnormally lateral tibial tubercle position, patella alta, hypermobility, or a secondary injury to the medial patellofemoral ligament (MPFL). There is an increasing interest in restoring normal anatomy to achieve stability, and at times more than 1 abnormality exists. This article describes the technique for combining a tibial tuberosity transfer and an MPFL reconstruction. The key features include planning of skin incisions to enable both operations to be undertaken, planning of the screw placement before osteotomy is performed and assessment of the joint through a superolateral portal to assess the need for MPFL reconstruction after tuberosity transfer.