Novel Framework for Quality Control in Vibration Monitoring of CNC Machining.

Vibrations are a common issue in the machining and metal-cutting sector, in which the spindle vibration is primarily responsible for the poor surface quality of workpieces. The consequences range from the need to manually finish the metal surfaces, resulting in time-consuming and costly operations, to high scrap rates, with the corresponding waste of time and resources. The main problem of conventional solutions is that they address the suppression of machine vibrations separately from the quality control process. In this novel proposed framework, we combine advanced vibration-monitoring methods with the AI-driven prediction of the quality indicators to address this problem, increasing the quality, productivity, and efficiency of the process. The evaluation shows that the number of rejected parts, time devoted to reworking and manual finishing, and costs are reduced considerably. The framework adopts a generalized methodology to tackle the condition monitoring and quality control processes. This allows for a broader adaptation of the solutions in different CNC machines with unique setups and configurations, a challenge that other data-driven approaches in the literature have found difficult to overcome.

A Biomechanical Comparison of Alternative Graft Preparations for All-Inside Anterior Cruciate Ligament Reconstruction.

PURPOSE: To biomechanically compare alternative graft constructs for all-inside anterior cruciate ligament (ACL) reconstruction in the event that the semitendinosus harvested is too narrow or too short to make a graft larger than 8 mm. METHODS: Bovine extensor tendons were used to make 6 different 9-mm-diameter grafts: traditional 4-strand, anastomosis 4-strand, 6-strand, 3-strand, button-fixation 4-strand, and loop-and-tack 4-strand grafts. The grafts were then subjected to cyclic biomechanical testing followed by failure loading. Force at 3 and 5 mm of displacement and ultimate force were recorded for all grafts. RESULTS: Compared with the traditional 4-strand graft, the only graft that showed significant biomechanical differences during the cyclic phase of testing was the button-fixation 4-strand graft, which was characterized by lower force at 3 mm of displacement (74 ± 34 N vs 122 ± 13 N, P = .004) and 5 mm of displacement (122 ± 35 N vs 172 ± 3 N, P = .006). During failure loading, ultimate force was significantly lower for both the 6-strand graft (491 ± 186 N, P = .041) and button-fixation 4-strand graft (326 ± 27 N, P < .001) than for the traditional 4-strand graft (778 ± 176 N). All other grafts were equivalent for the parameters tested. CONCLUSIONS: The anastomosis 4-strand, 3-strand, and loop-and-tack 4-strand grafts do not biomechanically differ in cyclic loading and ultimate force from traditional 4-strand grafts. This study supports the use of anastomosis 4-strand, 3-strand, or loop-and-tack 4-strand grafts in the event that a traditional all-inside 4-strand graft cannot be prepared from a harvested semitendinosus tendon in ACL reconstruction. CLINICAL RELEVANCE: This study tests and describes alternatives to the traditional 4-strand semitendinosus autograft for all-inside ACL reconstruction in the event that the harvested tendon is not adequate.

Knotless Suture Anchor With Suture Tape Quadriceps Tendon Repair Is Biomechanically Superior to Transosseous and Traditional Suture Anchor-Based Repairs in a Cadaveric Model.

PURPOSE: To compare the biomechanical properties of a knotless suture anchor with suture tape quadriceps tendon repair technique with transosseous and suture anchor repair techniques. METHODS: Twenty matched pairs of cadaveric knees underwent a quadriceps tendon avulsion followed by repair via the use of transosseous tunnels with #2 high-strength sutures, 5.5-mm biocomposite fully threaded suture anchors with #2 high-strength sutures, or 4.75-mm biocomposite knotless suture anchors with suture tape. Ten knees were repaired via transosseous repair and 10 via fully threaded suture anchor repair, and their matched specimens were repaired with suture tape and knotless anchors. Biomechanical analysis included displacement during cyclic loading over 250 cycles, construct stiffness, ultimate load to failure, and failure mode analysis. RESULTS: Compared with transosseous repairs, quadriceps tendons repaired with knotless suture tape demonstrated significantly less displacement during cyclic loading (cycles 1-20 3.6 ± 1.3 vs 6.3 ± 1.9 mm, P = .003; cycles 20-250 2.0 ± 0.4 vs 3.1 ± 0.9 mm, P = .011), improved construct stiffness (67 ± 25 vs 26 ± 12 N/mm, P = .001), and greater ultimate load to failure (616 ± 149 vs 413 ± 107 N, P = .004). Our repair technique also demonstrated improved biomechanical parameters compared with fully threaded suture anchor repair in initial displacement during cyclic loading (cycles 1-20 3.0 ± 0.8 vs 5.1 ± 0.9 mm, P < .001), construct stiffness (62 ± 20 vs 28 ± 10 N/mm, P = .001) and ultimate load to failure (579 ± 129 vs 399 ± 87 N, P = .006). CONCLUSIONS: Repair of quadriceps tendon ruptures with this knotless suture anchor with suture tape repair technique is biomechanically superior in cyclic displacement, construct stiffness, and ultimate load to failure compared with transosseous and fully threaded suture anchor techniques in cadaveric specimens. CLINICAL RELEVANCE: The demonstration that our repair technique is biomechanically superior to previously described techniques in a cadaveric setting suggests that consideration should be given to this technique.

Distal triceps knotless anatomic footprint repair: a new technique.

Distal triceps rupture is a rare injury causing significant disability. Several techniques for treating distal triceps ruptures have been described using bone tunnels or suture anchors. More recent techniques have focused on re-creating the anatomic footprint of the distal triceps tendon. However, the increasing numbers of anchors used increase the risk to the articular surface, and all earlier techniques require knot tying and bulky knots beneath the thin posterior elbow soft-tissue envelope. We describe a technique combining the use of bone tunnels and a single suture anchor to create a knotless anatomic footprint repair of the distal triceps. By using this technique, we are able to create a tension-band construct that self-reinforces the anatomic repair and is very low profile while significantly decreasing risk to the articular surface.

Distal triceps knotless anatomic footprint repair is superior to transosseous cruciate repair: a biomechanical comparison.

PURPOSE: The purpose of this study was to evaluate the biomechanical properties of a method of repair using bone tunnels with multiple high-strength nonabsorbable sutures and one knotless suture anchor compared with the standard transosseous technique for repair of the distal triceps. METHODS: The triceps tendon footprint was measured in 18 cadaveric elbows (9 matched pairs), and a distal tendon rupture was created. Eighteen elbows (9 matched pairs) were randomly assigned to one of 2 repair groups: transosseous cruciate repair group or knotless anatomic footprint repair group. Cyclic loading was performed for a total of 1,500 cycles and displacement was measured. Data for load at yield and peak load were obtained. RESULTS: The average bony footprint of the triceps tendon was 466 mm(2). Cyclic loading of tendons from the 2 repair types showed that the knotless anatomic footprint repair produced less displacement when compared with the transosseous cruciate repair (P < .05). Load at yield and peak load were also greater in the knotless anatomic footprint repair group (P < .05). CONCLUSIONS: Distal triceps knotless anatomic footprint repair in a cadaveric model had a significantly higher load and cycle to failure when compared with the traditional transosseous cruciate repair and produced less repair site motion. CLINICAL RELEVANCE: The increased biomechanical strength and resistance to displacement at the tendon-bone interface may lead to improved clinical outcomes with the knotless anatomic footprint repair technique and warrants further clinical study.