Shoulder The natural course after rotator cuff injury There is a large body of research focusing on how to maximize the prognosis of rotator cuff injuries, and Moosmayer evaluated clinical symptoms and rotator cuff morphologic changes in patients with asymptomatic total rotator cuff tears and found a potential risk of poor prognosis with non-surgical treatment. Many asymptomatic rotator cuff tears eventually develop into symptomatic rotator cuff tears, and the presence of corresponding symptoms often indicates increased rotator cuff tear, fatty infiltration, and muscle atrophy [1]. This study suggests that close clinical observation is needed for asymptomatic rotator cuff tears and that patients should be informed of the risks associated with non-surgical treatment. Rotator cuff repair The rotator cuff is often difficult to restore to its normal configuration after rotator cuff repair, and the incidence of this complication is higher in massive rotator cuff injuries [2-4]. Chung reported that although most patients showed significant clinical improvement regardless of rotator cuff healing, the rate of non-healing rotator cuff repair in massive rotator cuff injuries was as high as 39%, and fatty infiltration was a major risk factor for failure of rotator cuff healing [2]. Paxton conducted a 10-year follow-up study with results similar to Chung’s [3]. Kim et al [5] used edge repair sutures in 24 patients with massive rotator cuff tears and found a 47% retear rate at two years postoperative follow-up [5]. Weber evaluated whether platelet-rich fibrin matrix (PRFM) increased rotator cuff healing (an evidence-based level I study) and showed that one year postoperatively, the use of platelet-rich fibrin matrix (PRFM) had no significant effect on clinical outcomes or on the restoration of rotator cuff structural integrity [6]. A systematic review by Chahal on the ability of platelet-rich plasma to increase rotator cuff healing rates showed no significant benefit of platelet-rich plasma on either retear rates or various shoulder scores [7]. A recent prospective controlled clinical study using MRI with a two-year follow-up showed that allogeneic dermal cell grafts increased healing rates (85% vs. 40%) in massive rotator cuff injuries [8]. Superior glenoid labrum anterior-posterior (SLAP) injuries: repair or long head biceps tendonotomy? Provencher retrospectively analyzed 179 patients with type II SLAP injuries who underwent repair. 37% of patients had recurrence of symptoms and 28% required reoperation during the 4-year follow-up period [9]. Kim compared the clinical efficacy of repair and tendotomy in patients with rotator cuff injury combined with type II SLAP injury and showed that tendotomy was more reliable [10]. Shoulder instability The optimal treatment of shoulder instability remains controversial. A recent study showed better clinical outcomes and a better cost-benefit ratio for primary glenohumeral dislocation with one-stage arthroscopic fixation [11]. Another study investigated the natural course of bony Bankart injuries and found that within one year of initial dislocation, the unfixed fracture tended to resorb rapidly, resulting in glenoid bone loss [12]. In patients with refractory recurrent shoulder dislocations, especially those with 20-25% glenoid bone loss, it is controversial whether autologous or allogeneic bone grafts should be used for glenoid reconstruction; Yamamoto studied the mechanism of joint stability after Latarjet reconstruction in a cadaveric model and found that the sling effect played the most important role in increasing joint stability [13]. In biomechanical tests, Bhatia found that tibial remote articular surface grafts increased joint contact area and reduced joint stress peaks more than rostral grafts, resulting in better stabilization at 60 degrees of abduction or when the shoulder joint is in abduction and external rotation [14]. Millett arthroscopically treated 15 patients with bony Bankart injuries [16], in which an anchor nail was placed medial to the bone graft and the bone was fixed in place with sutures on the anchor nail. Only one patient had a re-dislocation due to a fall injury. In the case of lateral humeral defects, there has been a significant increase in the use of the Remplissage technique [17]. Cook studied the relationship between the position of the reconstruction tunnel and graft failure and found that 29% of grafts failed to be fixed at 7 weeks postoperatively, with overbuilt bone tunnels being a high risk factor for failure [19]. The highest bone density was found at the attachment point of the rostral clavicular ligament (20-60 mm distal to the clavicle), and failure rates were significantly higher beyond this point [20]. Anterior cruciate ligament of the knee Anterior cruciate ligament finger points and tunnel localization The anterior cruciate ligament has been the subject of the largest number of articles in this year’s knee sports medicine study. Although there is debate about the optimal bone tunnel location for ACL reconstruction, a large number of studies have focused on tunnel location for anatomic reconstruction. mcconkey surveyed 12 surgeons about their opinions on femoral tunnel location and found that there was no standardized criteria for the optimal location. However, the majority of surgeons believed that the femoral tunnel obtained by conventional transtibial positioning was more difficult to achieve anatomically reconstructed positions than medial approach positioning and outward inward positioning [21]. Many studies have compared the advantages and disadvantages of various femoral tunnel positioning techniques [22-25]. The main shortcoming of medial approach positioning is the tendency to shorten the length of the femoral tunnel [22,23]. Tompkins looked at the length of femoral tunnels created using medial approach positioning in 106 cases and found that femoral tunnels greater than 30 mm in length could be obtained in all cases while preserving the integrity of the posterior wall [22]. The revision rate was 5.16% for the medial approach technique, which was slightly higher than the transtibial tunnel technique (3.20%) [24]. The positioning of the tibial tunnel has also attracted widespread interest among clinicians, with many advocating a more anterior tibial tunnel than the traditional position.Hatayama designed an evidence-based Level IV study and found that ACL reconstruction with a more anterior tibial tunnel had better anterior stability and did not compromise joint extension [26]. It is controversial whether it makes sense to preserve the residual ACL after partial ACL rupture (single bundle rupture) with ACL preservation and strengthening. 55 patients with partial ACL rupture (38 with posterior external bundle strengthening and 17 with anterior internal bundle strengthening) were reviewed by Park and compared with 45 patients with double bundle reconstruction, showing no difference in anterior and rotational stability between the two groups [27]. The results showed no difference in the anterior and rotational stability of the joint between the two groups [27]. However, the diagnosis of ACL single-bundle fractures and how to perform single-bundle strengthening are technically challenging and require a great deal of experience. Preservation of the ACL tibial stump to facilitate vascularization of the graft and proprioceptive reconstruction has also been studied extensively. Hong conducted a prospective study of 90 patients with a two-year follow-up period and showed that preservation of the ACL stump did not affect knee stability, synovial re-covering of the ACL graft surface (vascularization), or proprioceptive recovery [28]. Treatment of pediatric ACL ruptures In recent years, more and more physicians are opting for reconstructive surgery for pediatric ACL ruptures, and there has been widespread clinician interest in how to perform ACL reconstruction in these patients with unclosed epiphyses [29,30].Kumar performed trans-epiphyseal ACL reconstruction using an autologous N-cord tendon in 32 patients with immature epiphyses, with excellent clinical outcomes at least until the age of 16 years. None of the patients developed limb inequality and only one patient developed mild valgus deformity [29]. Dumont found a clear increase in the rate of medial meniscal injury 150 days after ACL rupture, with both age and weight as risk factors for medial meniscal injury [31]. Incidence of osteoarthritis after ACL injury The primary goal of ACL reconstruction is to reduce the incidence of osteoarthritis in the knee after injury. Despite extensive research in this area, it has not been possible to demonstrate that ACL reconstruction bundles are more effective in reducing the incidence of osteoarthritis than non-surgical treatment [32,33]. The results of this study challenge the prevailing view that ACL reconstruction is effective in reducing the incidence of osteoarthritis, but it is noteworthy that the study excluded professional athletes and those less likely to participate in sports, a selection bias that somewhat affects the reliability of the findings [32]. It is also important to recognize that many other factors can influence the development of osteoarthritis, particularly meniscal and cartilage damage, so a large number of studies are still needed to verify the significance of ACL reconstruction for the relief of osteoarthritis. The ACL Study Group of the Multicenter Orthopaedic Clinical Outcomes Assessment Organization (MOON) reported 6-year follow-up results for ACL unibundle reconstruction, with 18.9% of patients re-treated for ACL injury in the affected knee and 10.2% of patients treated for the contralateral knee. Of these patients, 7.7% underwent ACL revision and 13.3% underwent cartilage-related treatment. The young age of the patient and the use of allograft tendons are risk factors for reoperation [34]. There are numerous studies comparing the results of single- and double-bundle ACL reconstruction, but to date, no study has demonstrated convincing evidence to suggest which technique is superior [35-37]. There was no significant difference in subjective patient scores [36]. ACL reconstruction graft selection The choice of autologous or allogeneic grafts for ACL reconstruction remains controversial; Ellis advocated the use of autologous grafts, especially in younger patients [38]. The authors compared reoperation rates after ACL reconstruction with autologous and allograft bone-patellar tendon-bone in an epiphyseal mature population and showed a 35% reoperation rate for allografts compared to 3% for autologous grafts one year after surgery [38]. However, some studies have reported acceptable results with allografts [39]. The best results for graft diameter are unknown, but a recent study using MRI and ultrasound imaging to assess the diameter of the N cord tendon preoperatively showed that both were accurate. The MRI assessment was most accurate when the image was magnified 4 times, and the accuracy of MRI at 2 times magnification did not differ from ultrasound assessment [40]. What factors can facilitate a faster return to sport in professional athletes is still being explored. A systematic analysis of postoperative rehabilitation after ACL reconstruction by Kruse showed that postoperative brace immobilization was unnecessary and had no clinical benefit, that a home rehabilitation program met the patient’s rehabilitation needs, and that neuromuscular stimulation, although safe, was not necessarily neuromuscular stimulation is safe but not necessarily effective [41]. Flanigan found that the majority of patients after ACL reconstruction did not return to their preoperative level of motion, that pain was the primary reason preventing return to sport, that half of the patients were afraid of re-injury, and that only a small percentage of patients felt that their knee function was adequate for work and family activities [42]. Posterior cruciate ligament Simple posterior cruciate ligament injuries Simple PCL injuries have been treated non-operatively in the past. 68 patients with acute simple PCL injuries treated non-operatively were followed up by Shelbourne for a minimum of 10 years and the results supported non-operative treatment, with all patients able to participate in sports with good strength, normal knee range of motion and satisfactory subjective patient scores in this case group. The incidence of moderate-to-severe osteoarthritis in this case group was 11%, although the study did not grade PCL laxity, and it is unclear whether nonsurgical treatment is effective in patients with severe PCL laxity and significant knee instability [43]. Some PCL injuries, either simple or combined with other ligament injuries, often require surgical reconstruction, and three articles this year have discussed surgical techniques and relevant anatomic landmarks for the purpose of anatomic reconstruction [44-46]. Therefore, for double-bundle reconstructions, they recommend locating the anterolateral femoral tunnel at the edge of the articular cartilage and the posterior medial femoral tunnel at 8.6 mm proximal to the articular cartilage, which is just remote from the medial intercondylar ridge. For single-bundle reconstruction, the femoral tunnel should be positioned at the midpoint of the anatomic stops of the anterolateral and posterior medial bundles [44]. PCL injury combined with posterior lateral horn injury Standardized treatment of PCL injury combined with posterior lateral horn injury remains a clinical challenge.Kim retrospectively investigated 65 patients and grouped patients by robust laxity to analyze posterior lateral rotational laxity, posterior stability, and clinical outcomes of the knee after PCL and posterior lateral horn reconstruction. The joint stability was examined using Telos gauges in the stress position camera, and no differences were found between groups in posterior stability and inversion stress stability of the joint, nor between groups in clinical scores and Dial test grading [47]. In patients with posterior lateral horn injury combined with mild posterior instability (<7 mm), Kim found in another study (evidence-based class III, 45 patients) that the joint was more stable in the stress position after PCL and posterior lateral horn reconstruction, with higher clinical scores and better function [48]. The biomechanical role of the meniscus in the knee, the efficacy of various treatments for different types of meniscal injuries, and the medium- to long-term outcomes after meniscal repair still deserve further confirmation. The maximum contact area of the lateral joint surface was not fully restored [49]. Nepple performed a meta-analysis of 13 included studies with a follow-up of more than five years, which showed similar failure rates (22.3%-24.3%) for the outside-in technique, inside-out technique, and total internal suture technique. No long-term results have been reported for the third-generation all-internal suture technique [50]. Meniscus transplantation Meniscus transplantation is an appropriate treatment option for specific populations, and current studies support the use of this technique in athletes with good short- and intermediate-term outcomes.Chalmers et al [51] reviewed the clinical outcomes of meniscus transplantation in 13 high-level athletes with a mean follow-up of 3.3 years, with 77% of patients returning to pre-injury professional sports and an additional 23% returning to meniscus-related surgery due to meniscal injury. The meniscus-related surgery was repeated in another 23% due to meniscal injury. A meniscal bioprosthesis was also reported this year with good results at 2-year follow-up, but this technique is still emerging and the medium- to long-term results are still uncertain [52]. Articular cartilage injuries Articular cartilage injuries remain a difficult clinical problem, and although many new techniques have emerged in recent years, all with encouraging results, the clinical perception of these new techniques remains mixed. The type of treatment used depends largely on the size of the cartilage defect, and Siston et al [53] reviewed the accuracy of different methods for assessing cartilage defects in the knee and showed that even the four most commonly used methods in clinical practice today have highly variable measurements, with only 57% accuracy of current measurements shown in this study. Campbell compared MRI and arthroscopic measurements of articular cartilage defects, using arthroscopic measurements as the gold standard [54], and found that MRI tended to underestimate articular cartilage damage, with MRI measurements being approximately 74% of the true area. There is still controversy as to when a cartilage graft can be weight-bearing [55-57]. In patients with autologous chondrocyte transplantation, Ebert designed a randomized controlled study (Level I) comparing the efficacy of early postoperative weight-bearing with conventional approaches [55] and found early weight-bearing and rapid rehabilitation to be safe and effective without adverse effects. Lee also found that weight-bearing at 2 weeks after microfracture surgery was safe and effective in patients with osteochondral defects of the talus [56]. Results of articular cartilage grafting Gudas reported a 10-year follow-up comparison of autologous osteochondral mosaic grafting and microfracture for knee cartilage injuries [58], which showed that autologous osteochondral mosaic grafting was significantly more effective than microfracture. Quantitative MRI is emerging as a means of evaluating cartilage repair after surgery. Bekkers used delayed enhancement magnetic resonance imaging (dGEMRIC) to evaluate TruFit cartilage grafts after one year [59] and showed that the bone plugs did not cause peripheral cartilage damage and that the new cartilage within the plugs had dGEMRIC characteristics. tompkins used allogeneic juvenile granular cartilage to treat Tompkins used allogeneic juvenile granular cartilage for the treatment of patellar Outerbridge grade 4 cartilage injury [60], with 73% of patients showing normal or near-normal grafted cartilage on MRI, with similarly satisfactory clinical outcomes, suggesting that allogeneic juvenile granular cartilage is a worthwhile option for this group of patients. Hip Imaging of acetabular femoral impingement syndrome and pathology of the acetabular glenoid labrum Many studies have emphasized the importance of combining history and physical examination in the diagnosis of acetabular femoral impingement syndrome (FAI).61,62 Register et al. investigated the incidence of bony abnormalities of the hip in an asymptomatic population and found that MRI revealed glenoid labral injury in 69% and cartilage injury in 24%. Schmitz also found that 80% of the asymptomatic population had imaging of glenoid labral injury and 20% had imaging of acetabular paraglenoid labral cysts [63]. In the asymptomatic population, 76% had imaging of acetabular hypertelorism, whereas only 64% of the FAI population had imaging of acetabular hypertelorism. This result suggests that, at least in women, acetabular hypertelorism may be a normal phenomenon [64]. In Schmitz's study of 180 asymptomatic hip patients [65], 92.8% had one FAI morphologic presentation and 52.2% had two FAI morphologic presentations. The timing of hip arthroscopy in patients with symptomatic FAI is unclear, and Hunt investigated the efficacy of non-surgical treatment in patients with intra-articular imaging changes but no osteoarthritic manifestations [66]. After one year, all patients, regardless of whether they eventually underwent surgery, showed significant improvement in pain symptoms and joint function compared to pre-treatment. This result suggests that a period of non-surgical treatment should be performed in patients without osteoarthritis before deciding to undergo surgery. McCormick used the modified Harris hip score as a criterion to explore whether age and arthritis were risk factors for preexisting lesions in hip arthroscopy [67], and showed that preoperative comorbid arthritis tended to suggest a lower postoperative hip score and that hip arthroscopy was more effective in patients younger than 40 years. The outcome of hip arthroscopy is better in patients younger than 40 years of age. Acetabular labral reconstruction has also attracted widespread interest among surgeons, but there is a lack of high-quality evidence to support this treatment [68,69]. Boykin reviewed the clinical outcomes of acetabular labral reconstruction and the rate of return to competitive sport [68] and found that 85.7% of patients were able to return to sport and 81% returned to the same level of sport as before the injury. Burchette achieved satisfactory results using thin femoral muscle reconstruction of the acetabular labrum [69]. Complications of hip arthroscopy Imaging has identified heterotopic ossification as one of the most concerning complications of hip arthroscopy, with some studies reporting rates as high as 44% [70]. Bedi studied 616 hip arthroscopies he performed and found that postoperative administration of indomethacin reduced the incidence of heterotopic ossification from 8.3% to 1.8% [71]. Acetabular labral injury is also a potential complication of hip arthroscopy, with an incidence of 20% reported in previous studies, but Domb recently reported an actual incidence of less than 1% [72]. Many previous studies have reported nerve injury during hip arthroscopy, and the Telleria intraoperative nerve detector was used to investigate the incidence of nerve injury, type of injury, and risk factors for sciatic nerve strain, ultimately finding that excessive traction weight was more likely to cause sciatic nerve palsy than prolonged traction and was the primary risk factor for sciatic nerve injury [73]. Prognosis With the widespread use of hip arthroscopy, it is particularly urgent to find appropriate indicators for evaluating clinical outcomes. The modified Harris hip score is currently the most used evaluation index [74], but in post-arthroscopic patients, the hip function score may more accurately reflect the functional and symptomatic changes in the joint after surgery [75]. [76], and found that although there was a correlation, there were some patients who were not satisfied with the outcome of the procedure, although the modified Harris hip score was in the "good - excellent" stage. Foot and ankle Talar cartilage injuries There is no widely accepted treatment for talar osteochondral injuries. Arthroscopic bone-marrow stimulation techniques, such as microfracture or retrograde drill decompression, are still the mainstay of first-line treatment, but it remains unclear whether the fibrocartilage induced by this technique can function as articular cartilage in the long term and meet the biomechanical requirements of the tibial talar joint [77]. van Bergen retrospectively analyzed 50 patients with primary femoral cartilage defects of the talus treated arthroscopically, all using In a retrospective analysis of 50 patients with arthroscopic treatment of primary femoral cartilage defects of the talus using arthroscopic debridement + bone-marrow stimulation technique, 94% of patients were able to function normally and 88% were able to exercise normally at a follow-up of 8-20 years. Therefore, the authors concluded that this technique is stable and reliable [78]. Achilles tendon In acute Achilles tendon rupture, the use of non-surgical treatment + functional exercise or surgical treatment is still controversial. A recent meta-analysis showed a similar incidence of re-rupture if ankle mobility was exercised early, with or without surgery. The absolute dedication to complications associated with surgical treatment increased by 15.8% and the final gastrocnemius circumference, strength and functional scores did not differ from non-surgical treatment. The authors therefore concluded that non-operative treatment is preferred for hospitals with active functional exercise rehabilitation centers. Surgical treatment is only recommended in those hospitals without a systematic functional exercise rehabilitation center [79]. Reconstruction of the ulnar collateral ligament has traditionally been performed using an autograft. However, Savoie recently used allograft N-tendon reconstruction in 123 throwing athletes with their modified postoperative rehabilitation exercises, and the patients returned to sports earlier (mean 9.5 months) with excellent Conway-Jobe scores in 83% of the patients [80]. There is also controversy as to whether partial ulnar collateral ligament injuries should be treated surgically, and a recent study found that platelet-rich plasma may be beneficial in the repair of partial ulnar collateral ligament injuries, with Podesta administering platelet-rich plasma locally to 34 athletes with partial ulnar collateral ligament ruptures on MRI, all of whom had poor outcomes with prior non-surgical treatment, and 30 patients were able to return to sports pain-free after platelet plasma treatment. After platelet plasma treatment 30 patients were able to return to pre-injury sports without pain, with only one case requiring elective reconstruction [81]. Elbow arthroscopy The development of elbow arthroscopic devices and techniques has allowed clinicians to gradually expand their clinical application. Due to the high level of neurovascular complications reported in the literature [82,83], many studies have investigated the incidence of nerve injury after elbow arthroscopic ulnar nerve release. 502 patients undergoing elbow arthroscopic ulnar nerve release were investigated by Blonna, and at 15 years of follow-up, only 24 patients had symptoms of transient nerve injury and none had symptoms of persistent nerve injury [82]. This study suggests that the risk of nerve injury is actually very low for senior elbow arthroscopic surgeons. The treatment of humeral epicondylitis is also still being explored, and although more and more surgeons are using elbow arthroscopy to treat humeral epicondylitis, the risk-benefit ratio is still unclear [84]. The role of platelet-rich plasma in this disease is also controversial; Krogh studied 60 patients and found that platelet-rich plasma therapy provided better pain relief than placebo and cortisol hormone therapy at the third-month follow-up, but there was no significant difference in clinical scores or ultrasonographic findings [85]. Cranial and spinal concussions How to reduce the incidence of concussions in sports, as well as other head injuries, is a current focus of media and physician attention. Recent studies have shown that direct head contact injuries are the leading cause of concussions in collegiate field hockey [86], and this study further supports that direct head contact injuries should be minimized in both professional and amateur athletes. Post-traumatic headache is a common complication of concussion, and Kontos found that patients with post-injury headaches or migraines required longer recovery times in collegiate football players [87], and Mihalik et al [88] made similar findings. Based on these findings, clinicians are deciding the timing of return to sports based on the type of migraine the patient has after a concussion. Disc degeneration and herniation in athletes In professional athletes, the incidence of disc disease is higher than in the general population due to repeated and increased stress over time [89]. In athletes with disc symptoms, clinical decisions should be made based on the mechanism of injury, severity of symptoms, and imaging, combined with the individual needs of the patient.Watkins used endoscopic discectomy to treat 75 athletes, and 67 returned to their previous sport level with an efficiency of 89%. The type of sport was not found to affect treatment success in this study.