Introduction. The human wrist is a highly complex joint, offering extensive motion across various planes. This study investigates scapholunate ligament (SLL) injuries’ impact on wrist stability and arthritis risks using cadaveric experiments and the finite element (FE) method. It aims to validate experimental findings with FE analysis results. Method. The study utilized eight wrist specimens on a custom rig to investigate Scapho-Lunate dissociation. Contact pressure and flexion were measured using sensors. A CT-based 3D geometry reconstruction approach was used to create the geometries needed for the FE analysis. The study used the Friedman test with pairwise comparisons to assess if differences between testing conditions were statistically significant. Result. The study found significant variations in scaphoid and lunate bone movement based on ligament condition. Full tears increased scapholunate distance in the distal-proximal direction and decreased in the medial-lateral direction. Lunate angles shifted from flexion to extension with fully torn ligaments. Conversely, the scaphoid shifted significantly from extension to flexion with full tears. A proximal movement was observed in the distal-proximal direction in all groups, with significant differences in the partial tear group. Lateral deviation of the scaphoid and lunate occurred with ligament damage, being more pronounced in the partial tear group. All groups exhibited statistically significant movement in the volar direction, with the full tear group showing the least movement. Also, radiocarpal joint and finger contact pressure and contact area were studied. Whereas the differences in contact area were not significant, scapholunate ligament tears resulted in significantly decreased finger contact pressures. FEA confirmed these findings, showing notable peak radiocarpal contact pressure differences between intact and fully torn ligaments. Conclusion. Our study found that SLL damage alters wrist stability, potentially leading to early arthritis. The FEA model confirmed these findings, indicating the potential for the clinical use of computer models from CT scans for treatment planning

Recent findings have identified the importance of previously undiagnosed or neglected meniscus lesions in association with anterior cruciate ligament (ACL) injuries (e.g. medial meniscus ramp lesions and posterior root tears of the lateral meniscus). There is increasing biomechanical evidence that they bear the potential to alter both anteroposterior and rotational laxity patterns in ACL injured knees. Few data exist with respect to the presence of these specific tear entities in large series of ACL injured patients. The purpose of the study was to analyze the meniscus tear pattern in a series of ACL injured knees with a special focus on ramp lesions of the medial meniscus and posterior root lesions of the lateral meniscus. The hypothesis was that a significant number of ACL injured patients would display these types of lesions. Data from 358 patients undergoing an ACL reconstruction (227 males /131 females, age: 28±10) were extracted from a center-based registry. The type of ACL tear (partial versus complete) as well as the presence of associated meniscus lesions were documented. Meniscus lesions were classified into the following categories: medial ramp lesions, lateral root lesions, medial ramp and lateral root lesion, other medial meniscus injuries, other lateral meniscus injuries, other bimeniscal injuries. Chi-square tests were used to determine whether the percentage of meniscal lesions differed between types of ACL tear, gender and age (below 21, 21–35, above 35). Significance was set at p < 0.05. Isolated ACL tears were present in 107 (30%) of the operated knees (31 partial; 327 complete). Complete ACL lesions were more likely to present an associated meniscus injury (321 out of 327, 71%) than partial tears (13 out of 31, 42%). The incidence of meniscus injuries which are associated with ACL tears is very high (70%). Previously undiagnosed or neglected meniscus injuries like medial ramp or lateral root tears could be identified in 35% of patients. As such, the hypothesis was confirmed that an important amount of ACL injured knees display this specific intraarticular soft tissue damage. A systematic evaluation of these lesions under arthroscopy should thus be performed and specific repair needs to be evaluated

Postoperative knee stability is critical in determining the success after reconstruction; however, only posterior and anterior stability is assessed. Therefore, this study investigates medial and lateral rotational knee laxity changes after partial and complete PCL tear and after PCL allograft reconstruction. The extending Lachman test assessed knee instability in six fresh-frozen human cadaveric knees. Tibia rotation was measured for the native knee, after partial PCLT (pPCLT), after full PCLT (fPCLT), and then after PCLR tensioned at 30° and 90°. In addition, tests were performed for the medial and lateral sides. The tibia was pulled with 130N using a digital force gauge. A compression load of 50N was applied to the joint on the universal testing machine (MTS Systems) to induce contact. Three-dimensional tibial rotation was measured using a motion capture system (Optotrak). On average, the tibia rotation increased by 33%-42% after partial PCL tear, and by 62%-75% after full PCL tear when compared to the intact case. After PCL reconstruction, the medial tibia rotation decreased by 33% and 37% compared to the fPCL tear in the case that the allograft was tensioned at 30° and 90° of flexion, respectively. Similarly, lateral tibial rotation decreased by 15% and 2% for allograft tensioned at 30° and 90° of flexion respectively, compared to the full tear. Rotational decreases were statistically significant (p<0.005) at the lateral pulling after tensioning the allograft at 90°. PCLR with the graft tensioned at 30° and 90° both reduced medial knee laxity after PCLT. These results suggest that while both tensioning angles restored medial knee stability, tensioning the Achilles graft at 30° of knee flexion was more effective in restoring lateral knee stability throughout the range of motion from full extension to 90° flexion, offering a closer biomechanical resemblance to native knee function

Though retear rates following rotator cuff repair are well established, we set out to review current literature to determine when early retears occurred (defined as <12m following surgery), and examine which pre- and post-operative variables might affect outcome. Pubmed, Medline, and CINAHL were searched for literature published from 2011 to 2021 using specific search terms. The inclusion criteria were studies reporting retear rates within 12 months of initial surgical repair. Exclusionary criteria were studies that included partial thickness tears, and studies that did not use imaging modalities within 12 months to assess for retears. PRISMA guidelines were followed, identifying a total of 10 papers. A combined total of 3372 shoulders included (Mean age 56 −67 years). The most common modality used to identify early retears were ultrasound scan and MRI. 6 of the 10 studies completed imaging at 0-3 months, 6 studies imaged at 3-6 months and 6 studies imaged at 6-12 months. Across all studies, there was a 17% early retear rate (574 patients). Of these, 13% occurred by 3 months, whilst the peak for retears occurred at 3-6 months (82%) and 5% occurred at 6-12 months. The risk of retear was higher in larger tears and extensive tendon degeneration. All studies apart from one documented a return to work/sport at 6 months post-operatively. Postoperative rehabilitation does not appear to alter retear rate, although data is limited with only 1 of 10 studies allowing active range of movement before 6 weeks. Retorn tendons had poorer functional outcomes compared to intact tendons at 12m following initial repair. The majority of early retears occur at 3-6 months and this time period should be prioritised both in rehabilitation protocols and future research. Age, tear size, and tendon degeneration were found to influence likelihood of early retears

In current practice in the UK there are three main approaches to investigating suspected scaphoid fractures not seen on initial plain film x-rays. Early MRI of all cases. Review all cases in clinic at two weeks with repeat x-rays. Hybrid model. Virtual Fracture Clinic (VFC) triage to reduce those who are seen in clinic at two weeks by:. ∘. Organising early MRI for those with high-risk presentation. ∘. Discharging those with an alternative more likely diagnosis. Our unit uses the VFC model. We aimed to evaluate its efficiency, safety, clinical outcomes and economic viability. All patients attending the emergency department with either a confirmed or suspected scaphoid fracture between March and December 2020 were included (n=305). Of these 297 were referred to the VFC: 33 had a confirmed fracture on x-ray and 264 had a suspected fracture. Of the suspected fractures reviewed in VFC 14% had an MRI organised directly owing to a high-risk presentation, 79% were brought for fracture clinic review and 17% discharged with an alternative diagnosis such as osteoarthritis. Of those subsequently reviewed in fracture clinic at two weeks: 9% were treated as scaphoid fractures (based on clinical suspicion and repeat x-rays), 17% had MRI or CT imaging organised, 5% did not attend and 69% were discharged. Overall, 17% of cases initially triaged, had further imaging – 41 MRIs and 5 CTs. MRI detected: 5% scaphoid fracture, 17% other fracture, 24% bone contusion, complete ligament tear 10%, partial ligament tear 39% and normal study 10%. The results of MRI minimally affected management. 3 patients were taken out of plaster early, 1 patient was immobilized who was not previously and no patients underwent operative management. In the following 12-month period one patient re-presented with a hand or wrist issue. This approach avoided 218 MRIs, equating to £24000 and 109 hours of scanner time. VFC triage and selective use of MRI scanning is a safe, efficient and cost-effective method for the management suspected scaphoid fractures. This can be implemented in units without the resource to MRI all suspected scaphoid fractures from the emergency department

Recent studies on animal models focused on the effect of preserving tendon remnant of rotator cuff on tendon healing. A positive effect by combining tendon remnant preservation and small bone vents on the greater tuberosity in comparison with standard tendon-to-bone repair has been shown. The purpose of the present clinical study was to evaluate the efficacy of biologic augmentation of arthroscopic rotator cuff repair by maintaining tendon remnant on rotator cuff footprint combined with small bone vents of the greater tuberosity. A retrospective study was conducted. All patients who underwent arthroscopic rotator cuff repair associated with small bone vents (nanofractures) and tendon footprint preservation were considered eligible for the study. Inclusion criteria were: diagnosis of full-thickness rotator cuff tear as diagnosed at preoperative magnetic resonance imaging (MRI) and confirmed at the time of surgery; minimum 24-month of follow-up and availability of post-operative MRI performed not earlier than 6 months after surgery. Exclusion criteria were: partial thickness tears, irreparable tears, capsulo-labral pathologies, calcific tendonitis, gleno-humeral osteoarthritis and/or previous surgery. Primary outcome was the ASES score. Secondary outcomes were: Quick-DASH and WORC scores, and structural integrity of repaired tendons by magnetic resonance imaging (MRI) performed six months after surgery. A paired t-test was used to compare pre- and postoperative clinical outcomes. Subgroup analysis was performed according to tear size. Significance was set at p < 0.05. The study included 29 patients (M:F = 15:14). Mean age (+ SD) of patients was 61.7 + 8.9 years. Mean follow-up was 27.4 ± 2.3 months. Comparison between pre- and postoperative functional scores showed significant clinical improvement (p < 0.001). Subgroup analysis for tear size showed significant differences in the QuickDASH score (0.04). Particularly, a significant difference in the QuickDASH score could be detected between medium and large tears (p=0.008) as well as medium and massive lesions (p=0.04). No differences could be detected between large and massive tears (p= 0.35). Postoperative imaging showed healed tendons in 21 out of 29 (72%) cases. Preservation of tendon remnant combined with small bone vents in the repair of medium-to-massive full-thickness rotator cuff tears provided significant improvement in clinical outcome compared to baseline conditions with complete structural integrity in 72% of the cases

The aim of this study was to investigate the occurrence of tissue hypoxia and apoptosis at different stages of tendinopathy and tears of the rotator cuff. We studied tissue from 24 patients with eight graded stages of either impingement (mild, moderate and severe) or tears of the rotator cuff (partial, small, medium, large and massive) and three controls. Biopsies were analysed using three immunohistochemical techniques, namely antibodies against HIF-1α (a transcription factor produced in a hypoxic environment), BNip3 (a HIF-1α regulated pro-apoptotic protein) and TUNEL (detecting DNA fragmentation in apoptosis). The HIF-1α expression was greatest in mild impingement and in partial, small, medium and large tears. BNip3 expression increased significantly in partial, small, medium and large tears but was reduced in massive tears. Apoptosis was increased in small, medium, large and massive tears but not in partial tears. These findings reveal evidence of hypoxic damage throughout the spectrum of pathology of the rotator cuff which may contribute to loss of cells by apoptosis. This provides a novel insight into the causes of degeneration of the rotator cuff and highlights possible options for treatment

Our aim was to evaluate bursal involvement at different stages of the impingement syndrome as judged by conventional histopathological examination and expression of tenascin-C, which is known to reflect active reparative processes in different tissues and disorders. Samples of subacromial bursa were taken from 33 patients with tendinitis, 11 with a partial tear and 18 with a complete tear of the rotator cuff, and from 24 control shoulders. We assessed the expression of tenascin-C, the thickness of the bursa, and the occurrence and degree of fibrosis, vascularity, haemorrhage and inflammatory cells. The expression of tenascin-C was significantly more pronounced in the complete tear group (p < 0.001) than in the partial tear, tendinitis or control groups. It was more pronounced in the tendinitis group than in the control group (p = 0.06), and there was more fibrosis in all the study groups than in the control group. The changes in the other parameters were not equally distinctive. Expression of tenascin-C did not correlate with the conventional histopathological parameters, suggesting that these markers reflect different phases of the bursal reaction. Tenascin-C seems to be a general indicator of bursal reaction, being especially pronounced at the more advanced stages of impingement and this reaction seems to be an essential part of the pathology of impingement at all its stages

Summary. When a TFCC tear is diagnosed, practitioners should maintain a high level of suspicion for the presence of a concomitant SL or LT ligament tear. Introduction. Disruption of the scapholunate (SL) or lunotriquetral (LT) ligament leads to dorsal and volar intercalated segment instability, respectively, while triangular fibrocartilage complex (TFCC) tears result in distal radioulnar joint (DRUJ) instability. Viegas et al. (1993) demonstrated that 56% of grossly visualised cadaveric wrists had one or more tears of a ligament or of the TFCC. The purpose of this investigation is to quantify the incidence, distribution, and correlation of SL, LT, and TFCC tears in a large group of cadaver wrists using magnetic resonance imaging (MRI). Additionally, statistical analysis was performed to predict. Methods. Spin density weighted, fat suppressed, and STIR MRI scans of the wrist were obtained in 48 fresh frozen cadaver arms using a 3 Tesla MRI scanner. The scans were scrutinised by one of us (PC) – a board certified musculoskeletal radiologist. The dorsal, volar, and membranous portions of the SL and LT ligaments were examined sequentially for the presence of a tear. Similarly, the central disk and radioulnar attachments of the TFCC were inspected for tears. Results. A ligament or the TFCC was labeled as torn if there was a complete tear, partial tear, or perforation of one or more of its components, but not if sole degenerative changes, thinning, or fraying of the fibers was observed. Four of the 48 images could not be interpreted due to unsatisfactory scans. The most prevalent injury was a TFCC tear, which was present in 28 (64%) of the 44 wrists examined. SL ligament tears were discovered in 20 (45%) of the wrists, and LT tears were present in 14 (32%) of the wrists. Moreover, 45% of the wrists examined had a TFCC tear and either a SL or LT ligament tear. Specifically, 50% of the 28 wrists with a TFCC tear had a concomitant LT tear, and 46% had a concomitant SL tear. Discussion. SL, LT, and TFCC tears were found in a substantial portion of the wrists examined. Moreover, the majority of wrists with a TFCC tear also had a SL or LT ligament tear. Viegas et al. found that 70% of wrists with a TFCC perforation also had a LT ligament tear. In our series, 71% had a TFCC tear, and 50% of those had a concomitant LT tear

Objectives

The effects of disease progression and common tendinopathy treatments on the tissue characteristics of human rotator cuff tendons have not previously been evaluated in detail owing to a lack of suitable sampling techniques. This study evaluated the structural characteristics of torn human supraspinatus tendons across the full disease spectrum, and the short-term effects of subacromial corticosteroid injections (SCIs) and subacromial decompression (SAD) surgery on these structural characteristics.

We assessed the predictive value of the macroscopic and detailed microscopic appearance of the coracoacromial ligament, subacromial bursa and rotator-cuff tendon in 20 patients undergoing subacromial decompression for impingement in the absence of full-thickness tears of the rotator cuff. Histologically, all specimens had features of degenerative change and oedema in the extracellular matrix. Inflammatory cells were seen, but there was no evidence of chronic inflammation. However, the outcome was not related to cell counts.

At three months the mean Oxford shoulder score had improved from 29.2 (20 to 40) to 39.4 (28 to 48) (p < 0.0001) and at six months to 45.5 (36 to 48) (p < 0.0001). At six months, although all patients had improved, the seven patients with a hooked acromion had done so to a less extent than those with a flat or curved acromion judged by their mean Oxford shoulder scores of 43.5 and 46.5 respectively (p = 0.046). All five patients with partial-thickness tears were within this group and demonstrated less improvement than the patients with no tear (mean Oxford shoulder scores 43.2 and 46.4, respectively, p = 0.04). These findings imply that in the presence of a partial-thickness tear subacromial decompression may require additional specific treatment to the rotator cuff if the outcome is to be improved further.

The purposes of this study were to define the range of laxity of the interosseous ligaments in cadaveric wrists and to determine whether this correlated with age, the morphology of the lunate, the scapholunate (SL) gap or the SL angle. We evaluated 83 fresh-frozen cadaveric wrists and recorded the SL gap and SL angle. Standard arthroscopy of the wrist was then performed and the grades of laxity of the scapholunate interosseous ligament (SLIL) and the lunotriquetral interosseous ligament (LTIL) and the morphology of the lunate were recorded. Arthroscopic evaluation of the SLIL revealed four (5%) grade I specimens, 28 (34%) grade II, 40 (48%) grade III and 11 (13%) grade IV. Evaluation of the LTIL showed 17 (20%) grade I specimens, 40 (48%) grade II, 28 (30%) grade III and one (1%) grade IV.

On both bivariate and multivariate analysis, the grade of both the SLIL and LTIL increased with age, but decreased with female gender. The grades of SLIL or LTIL did not correlate with the morphology of the lunate, the SL gap or the SL angle. The physiological range of laxity at the SL and lunotriquetral joints is wider than originally described. The intercarpal ligaments demonstrate an age-related progression of laxity of the SL and lunotriquetral joints. There is no correlation between the grades of laxity of the SLIL or LTIL and the morphology of the lunate, the SL gap or the SL grade. Based on our results, we believe that the Geissler classification has a role in describing intercarpal laxity, but if used alone it cannot adequately diagnose pathological instability.

We suggest a modified classification with a mechanism that may distinguish physiological laxity from pathological instability.