Quadriceps tendon autograft with or without bone block have comparable clinical outcomes, complications and revision rate for ACL reconstruction: a systematic review

Purpose: The purpose of this systematic review is to report complications, graft failure, fixation methods, rehabilitation protocol, clinical and patient-reported outcomes, and return to sports with the use of quadriceps tendon graft with the bone block (QT-B) and without bone block (QT-S). Methods: According to the PRISMA guidelines a comprehensive search was performed across PubMed/MEDLINE, Scopus, EMBASE, and Cochrane Library databases from inception until April 2022. Only prospective studies using quadriceps tendon autograft with a minimum of 20 patients were considered for inclusion. The outcome measures extracted from the studies were the KT-1000, Lysholm score, Subjective and Objective IKDC, Tegner, Marx Score, complications, failures and/or revision surgery, and rate of return to sports. Cochrane risk of bias and MINORS tool were used for the risk of bias assessment of all included studies. Results: A total of 13 studies were included, consisting of 5 randomized controlled trials, 6 cohort studies, 1 case–control and 1 case series. A total of 484 patients received QT-S in 6 studies of which 224 (46.2%) were males and 212 (43.8%) females with a mean age of 21.5 ± 7.5 (range 14–58). While 243 patients received QT-B in 7 studies of which 167 (68.7%) were males and 76 (31.3%) females with a mean age of 28.9 ± 4.5 (range: 18–49). The studies analyzed had a mean MINORS score of 14.6 (range, 12–19). Both QT-B and QT-S for ACL reconstruction reported satisfactory results in terms of patient-reported outcome measures. Although, a slightly higher anterior laxity was found with the QT-S than with the QT-B. Conclusion: Quadriceps tendon with a bone block (QT-B) or without bone block (QT-S) for ACL reconstruction is supported by current literature. Both grafts are safe and viable options for ACL reconstruction with comparable clinical outcomes, complications and revision rates. Level of evidence: Level IV. Registration: PROSPERO-CRD42022347134; https://www.crd.york.ac.uk/prospero

Revision ACL reconstruction in female athletes: current concepts

The challenge of revision anterior cruciate ligament (ACL) reconstruction lies in its complexity, varied presentation, and technical intricacies. A successful ACL reconstruction should allow patients to safely return to preinjury activities. However, it is only sometimes simple, and many risk factors and concurrent pathologies come into play. Evaluating and analysing the cause of failure and associated conditions is paramount to addressing them effectively. Despite a plethora of research and improvements in knowledge and technology, e gaps exist in issues such as optimal techniques of revision surgery, graft options, fixation, concurrent procedures, rehabilitation and protocol for return to sports of high-level athletes. Female athletes need additional focus since they are at higher risk of re-injury, suboptimal clinical outcomes, and lower rates of return to sport following revision reconstruction. Our understanding about injury prevention and the protection of ACL grafts in female athletes needs to be improved. This review focuses on the current state of revision ACL surgery in female athletes and provides recommendations and future directions for optimising outcomes in this high-risk group

Nitric oxide (NO) production in the upper airways is decreased in chronic sinusitis

The nasal concentration of nitric oxide (NO) was measured by chemiluminescence in healthy volunteers 3-68 years of age, and in patients suffering from common cold and chronic sinusitis. The concentration of NO in healthy subjects, 233.2 +/- 66.8 ppb (mean +/- SD), was found to be relatively independent of age and body size. The measured levels of NO did not differ between healthy volunteers and common cold patients, but they were significantly lower in patients suffering from chronic sinusitis, 96.4 +/- 72.8 ppb. As NO is a regulator of mucociliary activity and has bacteriostatic and antiviral effects, the decreased concentration of NO in patients suffering from sinusitis suggests that lack of NO may contribute to the pathogenesis of this disease. The importance of NO for the mucociliary system was emphasized by the finding that the 2 patients with the lowest nasal concentration of NO were found to manifest functional and morphological changes of the mucociliary system that are typical of acquired mucociliary dysfunction

Low levels of nasal nitric oxide (NO) correlate to impaired mucociliary function in the upper airways

Findings in previous studies have suggested nitric oxide (NO) to be a regulator of mucociliary activity in the upper airways. The aim of the present investigation was to study whether a correlation exists between the nasal NO concentration and mucociliary function in patients suffering from respiratory tract diseases such as chronic sinusitis or recurrent pneumonia. Nasal NO was measured with a chemiluminescence analyser, 100 ppb (parts per billion) being adopted as the lower limit of the normal range on the basis of findings in an earlier study of healthy subjects. Mucociliary function was evaluated by measurements of ciliary beat frequency (CBF) in nasal brush samples, and the saccharin transport test. A subnormal level of nasal NO was found in 50% (9/18) of the patients. This correlated with a significantly impaired mucociliary function, regarding both CBF and the saccharin transport time. The median CBF was 10.6 Hz in the group with normal levels of nasal NO, as compared to 8.4 Hz in the subnormal NO group. All patients with a normal nasal NO concentration had a mean CBF of > or = 9.0 Hz in their nasal brush samples, but in the subnormal group the same measurements yielded a CBF of > or = 9.0 Hz in only 22% (2/9) of the cases. As measured with the saccharin test, mucociliary transport was normal in 78% (7/9) in the normal nasal NO group, but the saccharin test was normal only in 11% (1/9) of the subnormal nasal NO group. Nasal NO levels were found to correlate with both CBF measurements (Spearman's rho, 0.80) and the saccharin transport test results (Spearman's rho, -0.61). The results of the present study provide further support for the view that NO is an important regulator of mucociliary function in the upper airways, and that measurements of the nasal NO concentration should be included in investigations of the mucociliary system

Recordings of mucociliary activity in vivo: Benefit of fast Fourier transformation of the photoelectric signal

Investigations of mucociliary activity in vivo are based on photoelectric recordings of light reflections from the mucosa. The alterations in light intensity produced by the beating cilia are picked up by a photodetector and converted to photoelectric signals. The optimal processing of these signals is not known, but in vitro recordings have been reported to benefit from fast Fourier transformation (FFT) of the signal. The aim of the investigation was to study the effect of FFT for frequency analysis of photoelectric signals originating from an artificial light source simulating mucociliary activity or from sinus or nasal mucosa in vivo, as compared to a conventional method of calculating mucociliary wave frequency, in which each peak in the signal is interpreted as a beat (old method). In the experiments with the artificial light source, the FFT system was superior to the conventional method by a factor of 50 in detecting weak signals. By using FFT signal processing, frequency could be correctly calculated in experiments with a compound signal. In experiments in the rabbit maxillary sinus, the spontaneous variations were greater when signals were processed by FFT. The correlation between the two methods was excellent: r = .92. The increase in mucociliary activity in response to the ciliary stimulant methacholine at a dosage of 0.5 microgram/kg was greater measured with the FFT than with the old method (55.3% +/- 8.3% versus 43.0% +/- 8.2%, p < .05, N = 8), and only with the FFT system could a significant effect of a threshold dose (0.05 microgram/kg) of methacholine be detected. In the human nose, recordings from aluminum foil placed on the nasal dorsum and from the nasal septa mucosa displayed some similarities in the lower frequency spectrum (< 5 Hz) attributable to artifacts. The predominant cause of these artifacts was the pulse beat, whereas in the frequency spectrum above 5 Hz, results differed for the two sources of reflected light, the mean frequency in seven healthy volunteers being 7.8 +/- 1.6 Hz for the human nasal mucosa. It is concluded that the FFT system has greater sensitivity in detecting photoelectric signals derived from the mucociliary system, and that it is also a useful tool for analyzing the contributions of artifacts to the signal

Triple Hybrid Tibial Anterior Cruciate Ligament Graft Fixation

Optimal graft fixation in anterior cruciate ligament reconstruction is critical. Several direct and indirect methods of graft fixation exist, each with advantages and disadvantages. This Technical Note describes a tibial hybrid anterior cruciate ligament graft fixation technique combining direct and indirect fixation methods, including autologous bone augmentation of the drill tunnel using cancellous bone fragments