Pathogenesis and prevention of posttraumatic osteoarthritis after intra-articular fracture

Exercise following joint distraction inhibits muscle wasting and delays the progression of post-traumatic osteoarthritis in rabbits by activating PGC-1α in skeletal muscle

OBJECTIVE

Muscle wasting frequently occurs following joint trauma. Previous research has demonstrated that joint distraction in combination with treadmill exercise (TRE) can mitigate intra-articular inflammation and cartilage damage, consequently delaying the advancement of post-traumatic osteoarthritis (PTOA). However, the precise mechanism underlying this phenomenon remains unclear. Hence, the purpose of this study was to examine whether the mechanism by which TRE following joint distraction delays the progression of PTOA involves the activation of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), as well as its impact on muscle wasting.

METHODS

Quadriceps samples were collected from patients with osteoarthritis (OA) and normal patients with distal femoral fractures, and the expression of PGC-1α was measured. The hinged external fixator was implanted in the rabbit PTOA model. One week after surgery, a PGC-1α agonist or inhibitor was administered for 4 weeks prior to TRE. Western blot analysis was performed to detect the expression of PGC-1α and Muscle atrophy gene 1 (Atrogin-1). We employed the enzyme-linked immunosorbent assay (ELISA) technique to examine pro-inflammatory factors. Additionally, we utilized quantitative real-time polymerase chain reaction (qRT-PCR) to analyze genes associated with cartilage regeneration. Synovial inflammation and cartilage damage were evaluated through hematoxylin-eosin staining. Furthermore, we employed Masson's trichrome staining and Alcian blue staining to analyze cartilage damage.

RESULTS

The decreased expression of PGC-1α in skeletal muscle in patients with OA is correlated with the severity of OA. In the rabbit PTOA model, TRE following joint distraction inhibited the expressions of muscle wasting genes, including Atrogin-1 and muscle ring finger 1 (MuRF1), as well as inflammatory factors such as interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in skeletal muscle, potentially through the activation of PGC-1α. Concurrently, the production of IL-1β, IL-6, TNF-α, nitric oxide (NO), and malondialdehyde (MDA) in the synovial fluid was down-regulated, while the expression of type II collagen (Col2a1), Aggrecan (AGN), SRY-box 9 (SOX9) in the cartilage, and superoxide dismutase (SOD) in the synovial fluid was up-regulated. Additionally, histological staining results demonstrated that TRE after joint distraction reduced cartilage degeneration, leading to a significant decrease in OARSI scores.TRE following joint distraction could activate PGC-1α, inhibit Atrogin-1 expression in skeletal muscle, and reduce C-telopeptides of type II collagen (CTX-II) in the blood compared to joint distraction alone.

CONCLUSION

Following joint distraction, TRE might promote the activation of PGC-1α in skeletal muscle during PTOA progression to exert anti-inflammatory effects in skeletal muscle and joint cavity, thereby inhibiting muscle wasting and promoting cartilage regeneration, making it a potential therapeutic intervention for treating PTOA.

A New Method for Creating Impact-Induced Intra-Articular Fractures in a Rabbit Model Induces Severe Post-Traumatic Osteoarthritis

OBJECTIVES

The objective of this work was to develop a model of intra-articular fracture (IAF) in a rabbit and document the speed and severity of degenerative joint changes after fracture fixation.

METHODS

With Institutional Animal Care & Use Committee approval, impact-induced IAFs were created in the distal tibia of 16 New Zealand White rabbits. Fractures were fixed with a plate and screws. Pain and function were monitored at regular postoperative intervals with limb loading analysis. Twelve or 26 weeks after fracture, animals were euthanized for histological assessment of cartilage degeneration and micro-computed tomography analysis of bone histomorphometry.

RESULTS

Eleven animals successfully completed the study. Maximum foot force in the fractured limb was 41% ± 21% lower than preoperative values ( P = 0.006) 12 weeks after fracture and remained 25% ± 13% lower ( P = 0.081) after 26 weeks. Cortical bone mineral density in micro-computed tomography images was 34% ± 13% lower 12 weeks after fracture ( P < 0.001) and remained (42% ± 8%) lower 26 weeks after fracture ( P < 0.001). Twelve weeks after fracture, Mankin scores of cartilage degeneration were significantly higher in the medial talus ( P = 0.007), lateral talus ( P < 0.001), medial tibia ( P = 0.017), and lateral tibia ( P = 0.002) of the fractured limb compared with the uninjured contralateral limb. Average Mankin scores in the talus increased from 12 to 26 weeks (5.9 ± 0.9 to 9.4 ± 0.4; P < 0.001 lateral; 5.4 ± 1.8 to 7.8 ± 2.0; P = 0.043 medial), indicating substantial and progressive joint degeneration.

CONCLUSIONS

The ankle joint of the New Zealand White rabbit provides the smallest available model of impact-induced IAF that can be treated with clinically relevant techniques and replicates key features of healing and degeneration found in human patients.

Advances in Understanding and Managing Floating Knee Injuries: A Comprehensive Review

Fractures of the ipsilateral tibia and femur, frequently combined with soft tissue damage and dislocations, describe floating knee injuries, a complicated orthopedic condition. Epidemiological data suggest that floating knee injuries account for a small but significant proportion of traumatic orthopedic injuries, with a higher incidence observed in younger males engaged in high-risk activities. Anatomically, floating knee injuries involve fractures of the femur and tibia, ligamentous disruptions, and soft tissue damage, contributing to the complexity and severity of these injuries. An extensive analysis of floating knee injuries is given in this paper, including information about epidemiology, anatomy, pathophysiology, categorization, management approaches, complications, prognosis, and current and upcoming developments.

Assessment of articular cartilage degradation in response to an impact injury using µMRI

PURPOSE

Degradation of articular cartilage (AC) due to injury to the knee joint may initiate post-traumatic osteoarthritis (PTOA). Failure to diagnose the onset of the disease at an early stage makes the cure ineffective for PTOA. This study investigated the consequences of a mechanical injury to the knee in a rabbit model using microscopic magnetic resonance imaging (µMRI) at high resolution.

MATERIALS AND METHODS

A mechanical injury was induced to the knee joints of 12 rabbits. Cartilage blocks were extracted from the non-impacted and impacted knee joints after 2 and 14 weeks post-impact. The specimens were studied using µMRI T2 relaxation and inductively coupled plasma analysis to determine the early degradation of the articular cartilage.

RESULTS

The data established a connection between T2 relaxation time and the early progression of knee PTOA after an impact injury. T2 values were found to be higher in the impacted cartilage at both 2 and 14 weeks, in particular, T2-55° values in the impacted samples displayed a significant rise of 6.93% after 2 weeks and 20.02% after 14 weeks. Lower glycosaminoglycan measurement and higher water content in the impacted cartilage confirmed the µMRI results.

CONCLUSIONS

This µMRI T2 study was able to detect cartilage damage in the impacted knees. In addition, greater degradation in the affected knees at 14 weeks than at 2 weeks indicated the progressive nature of cartilage deterioration over time. The µMRI results were in accord with the biochemical analysis, indicating the detection of early structural damage in the cartilage.

A Comprehensive Review on Managing Fracture Calcaneum by Surgical and Non-surgical Modalities

This comprehensive review delves into the multifaceted landscape of calcaneal fractures, thoroughly examining their aetiology, clinical presentation, and diverse management strategies. Encompassing surgical and non-surgical approaches, the review scrutinises critical aspects such as patient compliance, rehabilitation protocols, and long-term follow-up considerations. Surgical modalities, propelled by recent innovations like minimally invasive techniques and advanced fixation materials, are juxtaposed with non-surgical interventions, emphasising the pivotal role of patient education and adherence to optimise outcomes. The synthesis of critical findings underscores the need for individualised care and multidisciplinary collaboration in clinical practice. Moreover, the review outlines recommendations for healthcare practitioners and identifies promising areas for future research, including biomechanical studies and telerehabilitation. This comprehensive exploration aims to contribute to the ongoing evolution of calcaneal fracture management, ultimately enhancing patient care and outcomes in this complex orthopaedic realm.

Effect of anti-inflammatory treatments on patient outcomes and concentrations of inflammatory modulators in the post-surgical and post-traumatic tibiofemoral joint setting: a narrative review

Background and Objective

There are several anti-inflammatory therapeutic options that can be used in the context of post-surgical and post-traumatic knee settings. Each of these options carries with it certain benefits, as well as potential issues depending on the duration and administration of each therapy. An understanding of how these anti-inflammatory drugs modulate various biomarkers of inflammation is also necessary in understanding how they can affect patient and objective outcomes following acute knee injury or surgery. This review covers the many traditional therapeutic options that have been used in treating knee injuries, as well as some natural therapeutics that have shown anti-inflammatory properties.

Methods

A current review of the literature was conducted and synthesized into this narrative review.

Key Content and Findings

Many traditional anti-inflammatory therapeutics have been shown to be beneficial in both post-traumatic and post-surgical tibiofemoral joint settings at reducing inflammation and improving patient outcomes. However, many of these treatments have risks associated with them, which becomes problematic with prolonged, repeated administration. Natural anti-inflammatory compounds may also have some benefit as adjunctive treatment options in these settings.

Conclusions

There are multiple different therapeutic options that can be used in acute knee settings, but the specific mechanism of injury or surgical context should be weighed when determining the best clinical approach.

Conservative Treatment Using Platelet-Rich Plasma for Acute Anterior Cruciate Ligament Injuries in Highly Active Patients: A Retrospective Survey

Background The recommended treatment for anterior cruciate ligament (ACL) injuries in active, sports-oriented patients is reconstructive surgery in order to regain stability and prevent secondary meniscal injuries. However, ACL reconstruction requires a long recovery period and poses issues such as decreased muscle strength due to tendon harvesting and postoperative osteoarthritis (OA) progression, thereby raising significant expectations for the advancement of conservative treatments. Recent studies have shown that platelet-rich plasma (PRP) therapy, which utilizes the tissue repair-promoting property of platelets, is effective for ACL injuries. Methods We administered PRP therapy within six weeks after ACL injury in patients who expressed the desire for an early return to sports through conservative care. After the treatment, patients wore a simple brace that limited deep flexion but placed no restrictions on weight bearing. Four months was the standard goal established for returning to pre-injury condition, and, depending on the target level, timing, and knee condition, we adjusted the additional PRP treatments and rehabilitation approach, gradually authorizing the patients' return to sport. We assessed the ligament repair status by magnetic resonance imaging (MRI) just before the full return to sports. A retrospective survey was conducted to evaluate the status of ligament repair and the condition of return-to-sport in patients with ACL injuries who underwent conservative treatment using PRP. Results The average patient age was 32.7 years and the average treatment was 2.8 PRP sessions. MRI evaluations confirmed that ligament continuity was regained in all cases. All the patients returned to their pre-injury level (Tegner Activity Scale 7.0) in an average of 139.5 days, but there was one instance of re-rupture following the return to sports. Conclusion All patients with ACL injury who underwent PRP therapy regained ligament continuity and returned to sport successfully with only one case of re-rupture.

Osteoperiosteal Iliac Autograft Transplantation for Unreconstructable Tibial Plafond After Malunions of Pilon Fractures in Young Patients

BACKGROUND

Malunion of tibial pilon fracture, especially with a large cartilage loss of the tibial plafond, is a tough clinical conundrum. This study describes a joint-preserving technique that mainly involves corrective intraarticular osteotomy and osteoperiosteal iliac autograft transplantation for treating these generally considered unreconstructable tibial plafond.

METHODS

Sixteen patients with an average age of 33.6 years who were treated with this joint-preserving method between 2013 and 2020 were retrospectively analyzed. Ankle distraction was applied in all patients. Additional osteochondral autograft transplantation for talus was performed in 4 patients and supramalleolar osteotomy in 2 patients. The visual analog scale (VAS) score, the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, the 36-Item Short Form Health Survey (SF-36) score, and the ankle range of motion (ROM) were used for outcome analysis. Radiographic assessment was conducted, and the complications were recorded.

RESULTS

At a mean follow-up of 41.1 months, the mean VAS, AOFAS, and SF-36 scores improved from 6.3, 47.6, and 38.0 to 1.7, 84.4, and 70.8, respectively (P < .001 for each). The ankle ROM improved from 27.5 to 32.2 degrees (P = .023). The mean area of ilium blocks was 3.5 cm2, and the mean external fixation time was 94.1 days. Radiographs showed that good osteointegration was found in all patients and no significant progression of osteoarthritis in 15 patients. The major complications included poor incision healing in 2 patients and severe ankle stiffness in 2 patients, with one of them developing considerable varus-type osteoarthritis but reporting no pain. No deep infection, nonunion, or malunion occurred, and no secondary arthrodesis was performed during the final follow-up.

CONCLUSION

Osteoperiosteal iliac autograft transplantation might be an alternative surgical option for reconstructing unreconstructable malunited pilon fractures with a large cartilage loss of the tibial plafond in young patients.

LEVEL OF EVIDENCE

Level IV, case series.

Post-Traumatic Osteoarthritis, Psychological Health, and Quality of Life After Lower Limb Injury in U.S. Service Members

INTRODUCTION

The aims of this project were to assess (1) the prevalence and timing of post-traumatic osteoarthritis (PTOA) after a traumatic lower limb injury, (2) the risk of PTOA based on injury type, and (3) the association of PTOA with psychological health and quality of life (QoL).

MATERIALS AND METHODS

The Wounded Warrior Recovery Project (WWRP) database and the Expeditionary Medical Encounters Dataset were queried to identify service members injured during deployment. The Military Health System Data Repository was utilized to extract medical record data to identify individuals with PTOA. Data on PTSD, depression symptoms, and QoL were extracted from the WWRP.

RESULTS

Of the 2,061 WWRP participants with lower limb injuries, 124 (6%) were diagnosed with PTOA, with first PTOA diagnosis occurring 3.8 ± 3.1 years after injury. Of the injury categories identified, only fractures were associated with high odds of lower limb PTOA (adjusted odds ratio [OR] = 3.92, 95% confidence interval [CI]: 2.38, 6.44). Individuals with PTOA diagnoses reported lower QoL scores relative to those without PTOA (F(1,2057) = 14.21, B = -0.05, P < .05). Additionally, rates of PTSD and depression symptoms were high but not different between those with or without PTOA.

CONCLUSIONS

Despite a low prevalence of lower limb PTOA in our study, fractures increased the risk of PTOA after deployment-related injuries. Additionally, those with PTOA reported lower QoL scores relative to those without PTOA. The findings of this study highlight the personalized needs of patients with trauma beyond just the repair of the immediate injury.

Effect of Targeted Cytokine Inhibition on Progression of Post-Traumatic Osteoarthritis Following Intra-Articular Fracture

Intra-articular fractures (IAF) result in significant and prolonged inflammation, increasing the chances of developing post-traumatic osteoarthritis (PTOA). Interleukin-one beta (IL-1β) and Tumor Necrosis Factor-alpha (TNF-α) are key inflammatory factors shown to be involved in osteochondral degradation following IAF. As such, use of targeted biologics such as Infliximab (INX), a TNF-α inhibitor, and Anakinra (ANR), an interleukin-one (IL-1) receptor antagonist (IL1RA), may protect against PTOA by damping the inflammatory response to IAF and reducing osteochondral degradation. To test this hypothesis, IAFs were induced in the hindlimb knee joints of rats treated with INX at 10 mg/kg/day, ANR at 100 g/kg/day, or saline (vehicle control) by subcutaneous infusion for a period of two weeks and healing was evaluated at 8-weeks post injury. Serum and synovial fluid (SF) were analyzed for soluble factors. In-vivo microcomputed tomography (µCT) scans assessed bone mineral density and bone morphometry measurements. Cationic CA4+ agent assessed articular cartilage composition via ex vivo µCT. Scoring according to the Osteoarthritis Research Society International (OARSI) guidelines was performed on stained histologic tibia sections at the 56-day endpoint on a 0-6 scale. Systemically, ANR reduced many pro-inflammatory cytokines and reduced osteochondral degradation markers Cross Linked C-Telopeptide Of Type II (CTXII, p < 0.05) and tartrate-resistant acid phosphatase (TRAP, p < 0.05). ANR treatment resulted in increased chemokines; macrophage-chemotractant protein-1 (MCP-1), MPC-3, macrophage inhibitory protein 2 (MIP2) with a concomitant decrease in proinflammatory interleukin-17A (IL17A) at 14 days post-injury within the SF. Microcomputed tomography (µCT) at 56 days post-injury revealed ANR Treatment decreased epiphyseal degree of anisotropy (DA) (p < 0.05) relative to saline. No differences were found with OARSI scoring but contrast-enhanced µCT revealed a reduction in glycosaminoglycan content with ANR treatment. These findings suggest targeted cytokine inhibition, specifically IL-1 signaling, as a monotherapy has minimal utility for improving IAF healing outcomes but may have utility for promoting a more permissive inflammatory environment that would allow more potent disease modifying osteoarthritis drugs to mitigate the progression of PTOA after IAF.

Exposure of Tissue-Engineered Cartilage Analogs to Synovial Fluid Hematoma After Ankle Fracture Is Associated With Chondrocyte Death and Altered Cartilage Maintenance Gene Expression

BACKGROUND

The first stage of fracture healing consists of hematoma formation with recruitment of proinflammatory cytokines and matrix metalloproteinases. Unfortunately, when there is an intra-articular fracture, these inflammatory mediators are not retained at the fracture site, but instead, envelop the healthy cartilage of the entire joint via the synovial fluid fracture hematoma (SFFH). These inflammatory cytokines and matrix metalloproteinases are known factors in the progression of osteoarthritis and rheumatoid arthritis. Despite the known inflammatory contents of the SFFH, little research has been done on the effects of the SFFH on healthy cartilage with regard to cell death and alteration in gene expression that could lead to posttraumatic osteoarthritis (PTOA).

METHODS

SFFH was collected from 12 patients with intraarticular ankle fracture at the time of surgery. Separately, C20A4 immortalized human chondrocytes were 3-dimensionally cultured to create scaffold-free cartilage tissue analogs (CTAs) to simulate healthy cartilage. Experimental CTAs (n = 12) were exposed to 100% SFFH for 3 days, washed, and transferred to complete media for 3 days. Control CTAs (n = 12) were simultaneously cultured in complete medium without exposure to SFFH. Subsequently, CTAs were harvested and underwent biochemical, histological, and gene expression analysis.

RESULTS

Exposure of CTAs to ankle SFFH for 3 days significantly decreased chondrocyte viability by 34% (P = .027). Gene expression of both COL2A1 and SOX9 were significantly decreased after exposure to SFFH (P = .012 and P = .0013 respectively), while there was no difference in COL1A1, RUNX2, and MMP13 gene expression. Quantitative analysis of Picrosirius red staining demonstrated increased collagen I deposition with poor ultrastructural organization in SFFH-exposed CTAs.

CONCLUSION

Exposure of an organoid model of healthy cartilage tissue to SFFH after intraarticular ankle fracture resulted in decreased chondrocyte viability, decreased expression of genes regulating normal chondrocyte phenotype, and altered matrix ultrastructure indicating differentiation toward an osteoarthritis phenotype.

CLINICAL RELEVANCE

The majority of ankle fracture open reduction and internal fixation does not occur immediately after fracture. In fact, typically these fractures are treated several days to weeks later in order to let the swelling subside. This means that the healthy innocent bystander cartilage not involved in the fracture is exposed to SFFH during this time. In this study, the SFFH caused decreased chondrocyte viability and specific altered gene expression that might have the potential to induce osteoarthritis. These data suggest that early intervention after intraarticular ankle fracture could possibly mitigate progression toward PTOA.

Mismatch between Clinical-Functional and Radiological Outcome in Tibial Plateau Fractures: A Retrospective Study

BACKGROUND

The evaluation of tibial plateau fractures (TPF) encompasses the assessment of clinical-functional and radiological parameters. In this study, the authors aimed to investigate the potential correlation between these parameters by utilizing both the clinical-functional and the modified radiological Rasmussen score.

METHODS

In this retrospective monocentric study conducted at a level-I trauma center, patients who underwent surgery between January 2014 and December 2019 due to a TPF were included. The clinical-functional Rasmussen score prior to the injury, at 1-year postoperatively, and during the last follow-up (minimum 18 months) was assessed using a standardized questionnaire. Additionally, the modified radiological Rasmussen score was determined at the 1-year postoperative mark using conventional radiographs in two planes.

RESULTS

A total of 50 patients were included in this study, comprising 40% (n = 20) men, and 60% (n = 30) women, with an average age of 47 ± 11.8 years (range 26-73 years old). Among them, 52% (n = 26) had simple fractures (classified according to Schatzker I-III), while 48% (n = 24; according to Schatzker IV-VI) had complex fractures. The mean follow-up was 3.9 ± 1.6 years (range 1.6-7.5 years). The functional Rasmussen score assessed before the injury and at follow-up showed an "excellent" average result. However, there was a significant difference in the values of complex fractures compared to before the injury. One year postoperatively, both the clinical-functional score and the modified radiological score demonstrated a "good" average result. The "excellent" category was more frequently observed in the functional score, while the "fair" category was more common in the radiological score. There was no agreement between the categories in both scores in 66% of the cases.

CONCLUSIONS

The data from this retrospective study demonstrated that patients with TPF are able to achieve a nearly equivalent functional level in the medium-term after a prolonged recovery period, comparable to their pre-injury state. However, it is important to note that the correlation between clinical-functional and radiological parameters is limited. Consequently, in order to create prospective outcome scores, it becomes crucial to objectively assess the multifaceted nature of TPF injuries in more detail, both clinically and radiologically.

High Prevalence of Persistent Measurable Postoperative Knee Joint Laxity in Patients with Tibial Plateau Fractures Treated by Open Reduction and Internal Fixation (ORIF)

The development of post-traumatic osteoarthrosis after tibial plateau fracture (TPF) is multifactorial and can only be partially influenced by surgical treatment. There is no standardized method for assessing pre- and postoperative knee joint laxity. Data on the incidence of postoperative laxity after TPF are limited. The purpose of this study was to quantify postoperative laxity of the knee joint after TPF. Fifty-four patients (mean age 51 ± 11.9 years) were included in this study. There was a significant increase in anterior-posterior translation in 78.0% and internal rotation in 78.9% in the injured knee when compared to the healthy knee. Simple fractures showed no significant difference in laxity compared to complex fractures. When preoperative ligament damage and/or meniscal lesions were present and surgically treated by refixation and/or bracing, patients showed higher instability when compared to patients without preoperative ligament and/or meniscal damage. Patients with surgically treated TPF demonstrate measurable knee joint laxity at a minimum of 1 year postoperatively. Fracture types have no influence on postoperative laxity. This emphasizes the importance of recognizing TPF as a multifaceted injury involving both complex fractures and damage to multiple ligaments and soft tissue structures, which may require further surgical intervention after osteosynthesis.

A novel large animal model of posttraumatic osteoarthritis induced by inflammation with mechanical stability

OBJECTIVES

Animal models are needed to reliably separate the effects of mechanical joint instability and inflammation on posttraumatic osteoarthritis (PTOA) pathogenesis. We hypothesized that our modified intra-articular drilling (mIAD) procedure induces cartilage damage and synovial changes through increased inflammation without causing changes in gait.

METHODS

Twenty-four Yucatan minipigs were randomized into the mIAD (n=12) or sham control group (n=12). mIAD animals had two osseous tunnels drilled into each of the tibia and femur adjacent to the anterior cruciate ligament (ACL) attachment sites on the left hind knee. Surgical and contralateral limbs were harvested 15 weeks post-surgery. Cartilage degeneration was evaluated macroscopically and histologically. Synovial changes were evaluated histologically. Interleukin-1 beta (IL-1β), nuclear factor kappa B (NF-κB), and tumor necrosis factor alpha (TNF-α) mRNA expression levels in the synovial membrane were measured using quantitative real-time polymerase chain reaction. IL-1β and NF-κB levels in chondrocytes were assessed using immunohistochemistry. Load asymmetry during gait was recorded by a pressure-sensing walkway system before and after surgery.

RESULTS

The mIAD surgical knees demonstrated greater gross and histological cartilage damage than contralateral (P<.01) and sham knees (P<.05). Synovitis was present only in the mIAD surgical knee. Synovial inflammatory marker (IL-1β, NF-κB, and TNF-α) expression was three times higher in the mIAD surgical knee than the contralateral (P<.05). Chondrocyte IL-1β and NF-κB levels were highest in the mIAD surgical knee. In general, there were no significant changes in gait.

CONCLUSIONS

The mIAD model induced PTOA through inflammation without affecting gait mechanics. This large animal model has significant applications for evaluating the role of inflammation in PTOA and for developing therapies aimed at reducing inflammation following joint injury.

Development and characterization of an intra-articular fracture mediated model of post-traumatic osteoarthritis

PURPOSE

This study aimed to develop and characterize a closed intra-articular fracture (IAF) mediated post-traumatic osteoarthritis (PTOA) model in rats to serve as a testbed for putative disease modifying interventions.

METHODS

Male rats were subject to a 0 Joule (J), 1 J, 3 J, or 5 J blunt-force impact to the lateral aspect of the knee and allowed to heal for 14 and 56 days. Micro-CT was performed at time of injury and at the specified endpoints to assess bone morphometry and bone mineral density measurements. Cytokines and osteochondral degradation markers were assayed from serum and synovial fluid via immunoassays. Histopathological analyses were performed on decalcified tissues and assessed for evidence of osteochondral degradation.

RESULTS

High-energy (5 J) blunt impacts consistently induced IAF to the proximal tibia, distal femur, or both while lower energy (1 J and 3 J) impacts did not. CCL2 was found to be elevated in the synovial fluid of rats with IAF at both 14- and 56-days post-injury while COMP and NTX-1 were upregulated chronically relative to sham controls. Histological analysis showed increased immune cell infiltration, increased osteoclasts and osteochondral degradation with IAF relative to sham.

CONCLUSION

Based on results from the current study, our data indicates that a 5 J blunt-forced impact adequately and consistently induces hallmark osteoarthritic changes to the articular surface and subchondral bone at 56 days after IAF. Marked development of PTOA pathobiology suggest this model will provide a robust testbed for screening putative disease modifying interventions that might be translated to the clinic for militarily relevant, high-energy joint injuries.

Tramadol May Increase Risk of Hip Fracture in Older Adults with Post-Traumatic Osteoarthritis

Tramadol, an analgesic widely used for arthritic pain, is known to have adverse effects. This study investigated the association between the long-term use of tramadol for pain control and subsequent hip fractures in patients aged 60 years or older with posttraumatic osteoarthritis. This population-based retrospective cohort study included patients with posttraumatic osteoarthritis who received tramadol for pain control for more than 90 days within a 1-year period. A control cohort was enrolled using propensity score matching. The primary outcome was a new diagnosis of hip fracture requiring surgery. In total, 3093 patients were classified into each cohort. Tramadol use was identified as a risk factor for hip fracture (adjusted hazard ratio (aHR): 1.41; 95% confidence interval (CI): 1.09–1.82; p = 0.008), especially among patients aged 60–70 years (aHR: 2.11; 95% CI: 1.29–3.47; p = 0.003) and among male patients (aHR: 1.83; 95% CI: 1.24–2.70; p = 0.002). This is the first cohort study focusing on the association between long-term tramadol use and hip fracture among older adults with posttraumatic osteoarthritis. Tramadol, as a long-term pain control analgesic for older adults with posttraumatic osteoarthritis, may increase the risk of hip fracture, especially among male patients and those aged 60–70 years.

Autophagy in the pathogenesis and therapeutic potential of post-traumatic osteoarthritis

Autophagy, as a fundamental mechanism for cellular homeostasis, is generally involved in the occurrence and progression of various diseases. Osteoarthritis (OA) is the most common musculoskeletal disease that often leads to pain, disability and economic loss in patients. Post-traumatic OA (PTOA) is a subtype of OA, accounting for >12% of the overall burden of OA. PTOA is often caused by joint injuries including anterior cruciate ligament rupture, meniscus tear and intra-articular fracture. Although a variety of methods have been developed to treat acute joint injury, the current measures have limited success in effectively reducing the incidence and delaying the progression of PTOA. Therefore, the pathogenesis and intervention strategy of PTOA need further study. In the past decade, the roles and mechanisms of autophagy in PTOA have aroused great interest in the field. It was revealed that autophagy could maintain the homeostasis of chondrocytes, reduce joint inflammatory level, prevent chondrocyte death and matrix degradation, which accordingly improved joint symptoms and delayed the progression of PTOA. Moreover, many strategies that target PTOA have been revealed to promote autophagy. In this review,  we summarize the roles and mechanisms of autophagy in PTOA and the current strategies for PTOA treatment that depend on autophagy regulation, which may be beneficial for PTOA patients in the future.

A review of Risk Factors for Post-traumatic hip and knee osteoarthritis following musculoskeletal injuries other than anterior cruciate ligament rupture

Post-traumatic osteoarthritis (PTOA) is a common form of osteoarthritis that might occur after any joint trauma. Most PTOA publications mainly focus on anterior cruciate ligament (ACL) injuries. However, many other traumatic injuries are associated with PTOA, not only for the knee but also for the hip joint. We aim to identify and summarize the existing literature on the musculoskeletal injuries associated with knee and hip PTOA and their risk factors in determining those with a worse prognosis, excluding ACL injuries. Despite the narrative nature of this review, a systematic search for published studies in the last twenty years regarding the most relevant injuries associated with a higher risk of PTOA and associated risk factors for OA was conducted. This review identified the six more relevant injuries associated with knee or hip PTOA. We describe the incidence, risk factors for the injury and risk factors for PTOA of each. Meniscal injury, proximal tibial fracture, patellar dislocation, acetabular, femoral fractures and hip dislocations are all discussed in this review.

Operative strategy for tri-malleolar ankle fractures with posteromedial plafond involvement: a review of sixty six cases

PURPOSE

We aimed to summarize the radiographic and clinical outcomes in various conditions of tri-malleolar ankle fractures (TMFs) with posteromedial (PM) plafond involvement (TMF + PM) and determine the factors affecting their subjective clinical outcomes.

METHODS

Radiographic and clinical findings of 66 patients who underwent operative treatment for TMF + PM were retrospectively reviewed. The patients were classified into three groups according to the PM fracture line location. Type I fractures were defined when the PM fracture line extended medially beyond the PM corner of the distal tibia while type II fractures were those in which the PM fracture line was located laterally to the PM corner. Type III fractures were defined as medial malleolar avulsion fractures when the PM fracture integrated into the medial malleolus. Clinical outcomes were evaluated using a subjective rating scale (excellent, good, fair, poor, and bad). Satisfactory results were defined as excellent, good, and fair. Factors affecting satisfactory clinical outcomes were assessed using a binary logistic regression analysis. Independent variables included demographic, fracture-related, and operation-related factors and radiographic measurements at the final follow-up.

RESULTS

Satisfactory clinical outcomes were observed in 74.2% of the total patients; of these patients, 75.7% (28/37), 76.5% (13/17), and 66.7% (8/12) had type I, type II, and type III fractures, respectively. The binary logistic regression analysis revealed that age at the time of operation, number of incarcerated fragments (IFs), type of IFs, and postoperative articular step-offs (mm) were related to subjective clinical outcomes (all P < 0.05). A positive value for post-operative articular step-offs represented distal migration of the posterior malleolar fragments. The odds ratios for older age, increased numbers of IFs, rotated IFs, and positive articular step-offs were 0.936, 0.116, 0.020, and 0.295, respectively.

CONCLUSION

Because TMF + PM is highly unstable, a delicate approach is needed according to each patient's fracture condition. Although it is best to reduce the fractured articular surface, a negative step-off, rather than a positive step-off, would be more likely recommended if accurate reduction is impossible. This could be applied to manage IFs, especially when the IFs are rotated. Dimpling of the articular surface induced by the removal of a small IF was not related to unsatisfactory clinical outcomes.

Long-term outcomes after extension block pinning for fracture-dislocations of the proximal interphalangeal joint

IV.

Prevalence of and factors associated with osteoarthritis and pain in retired Olympians, with comparison to the general population: part 1 – the lower limb

Objectives

This study aims (1) to determine the prevalence of lower limb osteoarthritis (OA) and pain in retired Olympians; (2) to identify factors associated with their occurrence and (3) to compare with a sample of the general population.

Methods

3357 retired Olympians (median 44.7 years) and 1735 general population controls (40.5 years) completed a cross-sectional survey. The survey captured demographics, general health, self-reported physician-diagnosed OA, current joint/region pain and injury history (lasting >1 month). Adjusted OR (aOR) compared retired Olympians with the general population.

Results

The prevalence of (any joint) OA in retired Olympians was 23.2% with the knee most affected (7.4%). Injury was associated with increased odds (aOR, 95% CI) of OA and pain in retired Olympians at the knee (OA=9.40, 6.90 to 12.79; pain=7.32, 5.77 to 9.28), hip (OA=14.30, 8.25 to 24.79; pain=9.76, 6.39 to 14.93) and ankle (OA=9.90, 5.05 to 19.41; pain=5.99, 3.84 to 9.34). Increasing age and obesity were also associated with knee OA and pain. While the odds of OA did not differ between Olympians and the general population, Olympians with prior knee and prior hip injury were more likely than controls with prior injury to experience knee (1.51, 1.03 to 2.21 (Olympians 22.0% vs controls 14.5%)) and hip OA (4.03, 1.10 to 14.85 (Olympians 19.1% vs Controls 11.5%)), respectively.

Conclusions

One in four retired Olympians reported physician-diagnosed OA, with injury associated with knee, hip and ankle OA and pain. Although overall OA odds did not differ, after adjustment for recognised risk factors Olympians were more likely to have knee and hip OA after injury than the general population, suggesting injury is an occupational risk factor for retired Olympians.

Surgical Intervention in Neglected Ankle Fracture: A Case Report

Ankle fracture is common in active young males. Treating ankle fractures can be straightforward or much more complicated; treatment options include nonoperative management or open anatomical reduction with rigid internal fixation. Successful treatment will allow early mobilization to avoid complications. Inadequate treatment, either nonoperative or operative management, may result in malunited ankle fractures. However, malunited ankle fractures due to the delayed presentation are very rare. An 18-year-old male presented to the clinic with a history of twisting injury to his right ankle two years ago. The patient sought medical advice once after injury, applied a back slab, and was advised for operative intervention. He refused the surgical intervention and was lost in follow-up. After two years, he presented again with ankle deformity and swelling. Assessment at initial presentation includes fibula malunion, medial malleolus malunion, and widening of the ankle mortise with talar tilt. Fogel and Morrey's performance index was used to evaluate the biomechanical result postoperatively. Delayed open anatomical reduction and rigid internal fixation of malunited ankle fractures to achieve normal ankle alignment will delay the onset of future degenerative changes and minimize the chance for early arthrodesis. 

The Role of Mechanically-Activated Ion Channels Piezo1, Piezo2, and TRPV4 in Chondrocyte Mechanotransduction and Mechano-Therapeutics for Osteoarthritis

Mechanical factors play critical roles in the pathogenesis of joint disorders like osteoarthritis (OA), a prevalent progressive degenerative joint disease that causes debilitating pain. Chondrocytes in the cartilage are responsible for extracellular matrix (ECM) turnover, and mechanical stimuli heavily influence cartilage maintenance, degeneration, and regeneration via mechanotransduction of chondrocytes. Thus, understanding the disease-associated mechanotransduction mechanisms can shed light on developing effective therapeutic strategies for OA through targeting mechanotransducers to halt progressive cartilage degeneration. Mechanosensitive Ca2+-permeating channels are robustly expressed in primary articular chondrocytes and trigger force-dependent cartilage remodeling and injury responses. This review discusses the current understanding of the roles of Piezo1, Piezo2, and TRPV4 mechanosensitive ion channels in cartilage health and disease with a highlight on the potential mechanotheraputic strategies to target these channels and prevent cartilage degeneration associated with OA.

Mid-term Outcomes of Treatment of Fracture Dislocation of the Proximal Interphalangeal Joint with Gexfinger®-A New Dynamic External Fixator

Background: Fracture dislocations of the proximal interphalangeal joint (PIPJ) are challenging injuries and a dynamic external fixator frame is often used. We devised a dynamic external fixator device called the Gexfinger^® that allows greater control of the degree of traction. The aim of this study is to report the mid-term outcomes of this device. Methods: This is a retrospective study of patients with fracture dislocation of the PIPJ who were treated with the Gexfinger^® over a 3-year period. Clinical data with regard to the patient, the injury, treatment and period of follow-up were recorded. The outcome measures included time to return to work, arc of motion at the interphalangeal joints, grip strength, visual analogue score (VAS) for pain, patient satisfaction and complications. Results: We studied 26 patients (17 men and 9 women) with an average age of 38 years. The average articular surface involvement was 56%. The mean period between injury and surgery was 6 days and the frames were maintained for 5.5 weeks on average. The mean follow-up period was 8.5 weeks. All patients returned to work at an average of 7 weeks. The mean arc of motion at the PIPJ and distal interphalangeal joint (DIPJ) were 82° and 65°, respectively and the mean grip strength was 83% of the contralateral side. 22 patients reported no pain at the final follow-up. Fifteen patients were very satisfied, 8 satisfied and 3 unsatisfied. Two patients had stiffness of the PIPJ. Conclusions: The mid-term outcomes of the Gexfinger^® are similar to other methods of dynamic traction described in literature. It is modular, easy to assemble and allows a greater control of the degree of traction. In combination with additional screws and/or K-wires, it has allowed us to treat a wide spectrum of PIPJ fracture dislocations with good outcomes. Level of Evidence: Level IV (Therapeutic).

Minimally invasive treatment and internal fixation vs. extended lateral approach in calcaneus fractures of thalamic interest

The extended lateral side approach is a common technique in the surgical treatment of calcaneal fractures, with thalamic collapse offering a good exposure of the fractured site; however, it can be burdened with complications due to soft tissue trauma. The present study aimed to compare patients treated with minimally invasive osteosynthesis through a minimum lateral approach and internal fixation with patients that were treated using internal fixation with an extended lateral side approach in cases of intra-articular calcaneal fractures with thalamic fracture. Patients were evaluated preoperatively and postoperatively by performing clinical and imagistic examinations, with radiography scans of the anterior-posterior calcaneal profile and computer tomography. Furthermore, preoperative and postoperative analyses of the Böhler angle on the radiological profile, complications and duration of the hospital admission for both groups were performed. There were 36 patients (39 calcaneal fractures) in group 1 and 24 patients (29 calcaneal fractures) in group 2. The results demonstrated no statistically significant differences in the preoperative (P=0.72) and postoperative (P=0.20) Böhler angle values. The postoperative Böhler angle average values were 26.9 in group 1 and 29.3 in group 2. A total of 11 patients were treated with Kirschner wires inserted in the calcaneus, and in 2/ll cases, one of the brooches registered a migration movement. There were no cases of material migration in the fractures that were stabilized by inserting Kirschner brooches up to the astragalus and cuboid bones. Taken together, the results of the present study demonstrated no significant differences in the Böhler angle values between the minimally invasive and open reduction techniques. However, the antibiotic therapy period, as well as the infection rate were lower in patients that were treated using the minimally invasive technique, suggesting that this technique was superior with respect to lower complication rates and improved functional results.

Risk of total knee replacement after proximal tibia fracture: a register-based study of 7,841 patients

Background and purpose - Post-traumatic knee osteoarthritis following proximal tibia fracture (PTF) is a common complication that may lead to total knee replacement as secondary treatment (TKRS). We determined the risk of TKRS following PTF, whether treated nonoperatively or operatively, and compared the results with a 38-fold control group without prior PTF. Patients and methods - We identified all patients over 18 years of age in Finland with PTF treated during the period 2009-2018 from the Finnish Hospital Discharge Register (FHDR) and Finnish Arthroplasty Register (FAR). Age, sex, treatment method, follow-up time, and possible TKRS were recorded. Results - 7,701 patients were treated for PTF during the period 2009-2018. Over the 5.1-year (SD 3.1) follow-up, TKRS was performed in 340 (4.3%) patients with a prior PTF after a mean of 2.1 (SD 2.0) years post-fracture. TKRS was needed in 138 (3.7%, HR 1.8) patients in the nonoperatively treated group and in 202 (5.0%, HR 3.2) patients in the operatively treated group. Operative treatment, female sex, and high age were identified as risk factors for TKRS. The incidence of TKRS was highest during the first 2 years after fracture and remained elevated throughout the follow-up. Interpretation - Patients with a prior PTF had a 1.8- to 3.2-fold higher risk of TKRS compared with controls during the first 5 years post-fracture. Risk of TKRS was associated with an operatively treated PTF, female sex, and high age. The patients in the operative group likely sustained more complex fractures, while female sex and age may be explained by more osteoporotic bone quality.

Primary total knee replacement for tibial plateau fractures in older patients: a systematic review of 197 patients

INTRODUCTION

Tibial plateau fractures are typically treated with osteosynthesis. In older patients, osteosynthesis is associated with some complications, risk of post-traumatic osteoarthritis and long partial, or non-weight bearing during the recovery phase. To avoid these problems, primary total knee replacement (TKR) has become an increasingly common treatment option. The aim of this study was to evaluate all the relevant literature and summarize the current evidence-based knowledge on the treatment of tibial plateau fractures with primary TKR in older patients.

MATERIALS AND METHODS

A systematic literature search of studies on total knee replacement (TKR) as primary treatment for acute traumatic tibial plateau fracture was conducted using OVID Medline, Scopus, and Cochrane databases from 1946 to 18 November 2019. We included all studies without restrictions regarding total knee replacement (TKR) as primary treatment for acute traumatic tibial plateau fracture.

RESULTS

Of the 640 reviewed articles, 16 studies with a total of 197 patients met the inclusion criteria. No controlled trials were available, and the overall quality of the literature was low. The results, using different clinical scoring systems, were good or fair. Four-year follow-up complication (6.1%) and revision (3.6%) rates after primary TKR appeared to be lower than after secondary TKR (complication rate 20-48%, revision rate 8-20%) but higher than after elective primary TKR.

CONCLUSION

Based on low-quality evidence, TKR appears to be a useful treatment option for tibial plateau fractures in older patients. Controlled trials are mandatory to determine the relative superiority of these two options as primary treatment of tibial plateau fractures in older patients.

Long-Term Incidence of Total Knee Arthroplasty after Open Reduction and Internal Fixation of Proximal Tibial and Distal Femoral Fractures: A Nationwide Cohort Study

Knee fractures often require open reduction internal fixation (ORIF) for knee function recovery. More than one fifth of patients with knee fractures subsequently develop posttraumatic arthritis, and over 5% of them need total knee arthroplasty (TKA). We conducted this nationwide retrospective cohort study using the data of 2,000,000 people in the general population who received TKA and were followed up in the 17-year period 2001-2017, through random sampling of the Taiwan National Health Insurance Research Database. We matched the ORIF and non-fracture groups by a propensity score, based on age, sex, index date of surgery, and comorbidities enrolled in CCI calculated at a 1:1 ratio. The average proportion of subjects receiving TKA after ORIF for distal femoral or proximal tibial fractures was 2.0 per 1000 person-years, which was significantly higher than that in the non-fracture group. Patients aged 20-65 years and males represented a significantly higher proportion of subjects receiving TKA after ORIF than that in the non-fracture group. The proportion of subjects receiving TKA for the 20-65-year subgroup of the ORIF group was 4%, and that for the male subgroup was 1.5%; both rates increased over the 17-year follow-up period. More aggressive intraoperative and postoperative adjuvant therapies may be necessary for these subgroups.

Altered Glenohumeral Biomechanics in Proximal Humeral Fracture Malunion

INTRODUCTION

There is little biomechanical evidence to support the traditional guideline that 45° represents acceptable proximal humerus deformity. We evaluated glenohumeral contact pressure (GP) and area, subacromial contact pressure, and joint abduction to assess biomechanical changes with different proximal humerus deformities.

METHODS

Fifteen fresh-frozen cadaver shoulders were used. Intact specimens were tested on a custom dynamic shoulder frame. Subsequently, a surgical neck fracture was made in each specimen and fixed using a custom dual hinge plate for fixation of 15°, 30°, and 45° deformities in varus, valgus, antecurvatum, retrocurvatum, and combined varus-antecurvatum and valgus-retrocurvatum. Specimens were then retested.

RESULTS

Compared with the intact state, GP was markedly lower with all levels of varus and varus-antecurvatum deformity. Valgus and combined valgus-retrocurvatum deformity of 45° led to notable increases in GP compared with the intact state. Varus deformities of 30° and 45° caused significant increases in subacromial pressures and limited abduction markedly from 60° to 54.2° and 44.6° (P < 0.001).

DISCUSSION

Varus and antecurvatum proximal humerus deformities as small as 15° were associated with notable alterations in glenohumeral joint mechanics. With valgus and retrocurvatum deformity, statistically significant joint alterations occurred only at higher deformity levels.

Post-traumatic osteoarthritis progression is diminished by early mechanical unloading and anti-inflammatory treatment in mice

OBJECTIVE

Post-traumatic osteoarthritis (PTOA) is a degenerative joint disease initiated by injury. Early phase (0-7 days) treatments often include rest (unloading) and anti-inflammatory medications, but how those early interventions impact PTOA progression is unknown. We hypothesized that early unloading and anti-inflammatory treatment would diminish joint inflammation and slow PTOA progression.

DESIGN

Mice were injured with non-invasive ACL rupture followed by hindlimb unloading (HLU) or normal cage activity (ground control: GC) for 7 days, after which all mice were allowed normal cage activity. HLU and GC mice were treated with daily celecoxib (CXB; 10 mg/kg IP) or vehicle. Protease activity was evaluated using in vivo fluorescence imaging, osteophyte formation and epiphyseal trabecular bone were quantified using micro-computed tomography, and synovitis and articular cartilage were evaluated using whole-joint histology at 7, 14, 21, and 28 days post-injury.

RESULTS

HLU significantly reduced protease activity (-22-30% compared to GC) and synovitis (-24-50% relative to GC) at day 7 post-injury (during unloading), but these differences were not maintained at later timepoints. Similarly, trabecular bone volume was partially preserved in HLU mice at during unloading (-14-15% BV/TV for HLU mice, -21-22% for GC mice relative to uninjured), but these differences were not maintained during reloading. Osteophyte volume was reduced by both HLU and CXB, but there was not an additive effect of these treatments (HLU: -46%, CXB: -30%, HLU + CXB: -35% relative to vehicle GC at day 28).

CONCLUSIONS

These data suggest that early unloading following joint injury can reduce inflammation and potentially slow PTOA progression.

Investigation of an injectable gold nanoparticle extracellular matrix

Post-traumatic osteoarthritis (PTOA) is a progressive articular degenerative disease that degrades articular cartilage and stimulates apoptosis in chondrocyte cells. An injectable decellularized, extracellular matrix (ECM) scaffold, that might be able to combat the effects of PTOA, was developed where the ECM was conjugated with 20 nm gold nanoparticles (AuNP) and supplemented with curcumin and hyaluronic acid (HA). Porcine diaphragm ECM was decellularized and homogenized; AuNPs were conjugated using chemical crosslinking followed by mixing with curcumin and/or HA. Injection force testing and scanning electron microscopy with energy-dispersive X-ray spectroscopy were utilized to characterize the ECM scaffolds. In vitro testing with L929 murine fibroblasts, equine synovial fibroblasts, and Human Chondrocytes were used to determine biocompatibility, reactive oxygen species (ROS) reduction, and chondroprotective ability. The results demonstrated that conjugation of 20 nm AuNPs to the ECM was successful without significantly altering the physical properties as noted in the low injection force. In vitro work provided evidence of biocompatibility with a propensity to reduce intracellular ROS and an ability to mitigate apoptosis of chondrocyte cells stimulated with IL-1β, a known apoptosis inducing cytokine. It was concluded that an injectable AuNP-ECM may have the ability to mitigate inflammation and apoptosis.

Tibial plateau fractures-Does non anatomic reduction lead to an adverse outcome? A 10-year follow-up

PURPOSE

Assess the effect of residual intra-articular step and limb alignment on the outcomes of operated tibial plateau fractures.

METHODS

After retrospectively enrolling 123 cases of operated tibial plateau fracture whole limb weight bearing X-rays of both knees and computed tomography scan was done to record the presence of knee osteoarthritis (OA), alignment and articular step. The Rasmussen functional score (RFS) and Visual Analogue scale (VAS) score was calculated. Depending on the articular step there were four groups, group A (no step), group B (<2 mm), group C (2 mm-5 mm) and group D (6 mm-10 mm). The patients were also divided into 3 groups based on knee alignment, group 1 (0-10° valgus angle), group 2 (varus angle upto 5°) and group 3 (varus angle of 5-15°).

RESULTS

Group A had 53, group B 31, group C 23 and group D 16 cases. The mean follow up was 10.23 years. The difference in the RFS/VAS score and OA rate amongst the 4 groups based on articular step had a P>0.05. Based on knee alignment RFS and OA rate amongst three groups had a P<0.05 with better results in group 1.

CONCLUSIONS

Mal-alignment is a more important predictor of outcome in operated tibial plateau fractures than articular step.

Fracture location impacts opioid demand in upper extremity fracture surgery

INTRODUCTION

Opioid sparing protocols should be formulated with appropriate demand. Specific fracture location has been hypothesized as an important predictor of post-operative pain. The purpose of this study is to evaluate the impact of fracture location on perioperative opioid demand after surgery with the hypothesis that this factor would be significantly associated with perioperative opioid demand in upper extremity fracture surgery.

METHODS

A national database was used to identify1-month pre-operative to 1-year postdischarge opioid demand in oxycodone 5-mg equivalents in 336,493 patients undergoing fracture fixation of the clavicle through distal radius between 2010 and 2020. Three timeframes were evaluated: 1-month pre-op to 90-days post-discharge, 3 months post-discharge to 1-year post-discharge, and 1-month pre-op to 1-year postdischarge. Multivariable main effects linear and logistic regression models were constructed to evaluate the changes in opioids filled, opioid prescriptions, and odds of two or more opioid prescriptions in these timeframes based on fracture location with adjustment for age, sex, obesity, pre-operative opioid usage, and polytrauma.

RESULTS

Compared to distal radius fracture fixation, fixation of elbow, distal humerus, humeral shaft, and proximal humerus fractures were associated with large, significant increases in 1-month pre-op to 1-year post-discharge opioid filling (33.5 - 63.4 additional oxycodone 5-mg equivalents, all p<0.05) and number of filled prescriptions (0.33 - 0.92 additional prescriptions, all p<0.05) compared to patients with other operatively treated upper extremity injuries.

DISCUSSION

Fracture location was a significant predictor of perioperative opioid demand. Elbow, distal humerus, humeral shaft, and proximal humerus fracture fixation was associated with the largest increases in opioid demand after upper extremity fracture fixation. Patients with these injuries may be at highest risk of extensive opioid consumption.

LEVEL OF EVIDENCE

Level III, retrospective, observational cohort study.

Regenerative Engineering Animal Models for Knee Osteoarthritis

Abstract

Osteoarthritis (OA) of the knee is the most common synovial joint disorder worldwide, with a growing incidence due to increasing rates of obesity and an aging population. A significant amount of research is currently being conducted to further our understanding of the pathophysiology of knee osteoarthritis to design less invasive and more effective treatment options once conservative management has failed. Regenerative engineering techniques have shown promising preclinical results in treating OA due to their innovative approaches and have emerged as a popular area of study. To investigate these therapeutics, animal models of OA have been used in preclinical trials. There are various mechanisms by which OA can be induced in the knee/stifle of animals that are classified by the etiology of the OA that they are designed to recapitulate. Thus, it is essential to utilize the correct animal model in studies that are investigating regenerative engineering techniques for proper translation of efficacy into clinical trials. This review discusses the various animal models of OA that may be used in preclinical regenerative engineering trials and the corresponding classification system.

Lay Summary

Osteoarthritis (OA) of the knee is the most common synovial joint disease worldwide, with high rates of occurrence due to an increase in obesity and an aging population. A great deal of research is currently underway to further our understanding of the causes of osteoarthritis, to design more effective treatments. The emergence of regenerative engineering has provided physicians and investigators with unique opportunities to join ideas in tackling human diseases such as OA. Once the concept is proven to work, the initial procedure for the evaluation of a treatment solution begins with an animal model. Thus, it is essential to utilize a suitable animal model that reflects the particular ailment in regenerative engineering studies for proper translation to human patients as each model has associated advantages and disadvantages. There are various ways by which OA can occur in the knee joint, which are classified according to the particular cause of the OA. This review discusses the various animal models of OA that may be used in preclinical regenerative engineering investigations and the corresponding classification system.

Anti-Inflammatory Therapeutic Approaches to Prevent or Delay Post-Traumatic Osteoarthritis (PTOA) of the Knee Joint with a Focus on Sustained Delivery Approaches

Inflammation plays a central role in the pathogenesis of knee PTOA after knee trauma. While a comprehensive therapy capable of preventing or delaying post-traumatic osteoarthritis (PTOA) progression after knee joint injury does not yet clinically exist, current literature suggests that certain aspects of early post-traumatic pathology of the knee joint may be prevented or delayed by anti-inflammatory therapeutic interventions. We discuss multifaceted therapeutic approaches that may be capable of effectively reducing the continuous cycle of inflammation and concomitant processes that lead to cartilage degradation as well as those that can simultaneously promote intrinsic repair processes. Within this context, we focus on early disease prevention, the optimal timeframe of treatment and possible long-lasting sustained delivery local modes of treatments that could prevent knee joint-associated PTOA symptoms. Specifically, we identify anti-inflammatory candidates that are not only anti-inflammatory but also anti-degenerative, anti-apoptotic and pro-regenerative.

Exploring partial intrinsic and extrinsic symmetry in 3D medical imaging

We present a novel methodology to detect imperfect bilateral symmetry in CT of human anatomy. In this paper, the structurally symmetric nature of the pelvic bone is explored and is used to provide interventional image augmentation for treatment of unilateral fractures in patients with traumatic injuries. The mathematical basis of our solution is based on the incorporation of attributes and characteristics that satisfy the properties of intrinsic and extrinsic symmetry and are robust to outliers. In the first step, feature points that satisfy intrinsic symmetry are automatically detected in the Möbius space defined on the CT data. These features are then pruned via a two-stage RANSAC to attain correspondences that satisfy also the extrinsic symmetry. Then, a disparity function based on Tukey's biweight robust estimator is introduced and minimized to identify a symmetry plane parametrization that yields maximum contralateral similarity. Finally, a novel regularization term is introduced to enhance similarity between bone density histograms across the partial symmetry plane, relying on the important biological observation that, even if injured, the dislocated bone segments remain within the body. Our extensive evaluations on various cases of common fracture types demonstrate the validity of the novel concepts and the accuracy of the proposed method.

Factors associated with perioperative opioid demand in lower extremity fractures: Does consumption vary by anatomic location?

INTRODUCTION

Perioperative opioid pain management protocols should reflect anticipated patient need. Fracture location and external fixation may be related to post-operative pain. The purpose of this study is to evaluate the impact of fracture location, articular injury, and pre-operative external fixation, and articular injury on perioperative opioid demand following definitive fixation.

METHODS

1-month pre-operative to 1-year post-discharge opioid demand in oxycodone 5-mg equivalents in 23,441 patients undergoing fracture fixation of the femoral shaft through ankle between 2007 and 2017 was evaluated using a national database. Opioid demand was compiled over several timeframes: 1-month pre-op to 90-days post-discharge, 3 months post-discharge to 1-year post-discharge, and 1-month pre-op to 1-year post-discharge. Multivariable main effects linear and logistic regression models were constructed to evaluate the increased opioids filled, increased opioid prescriptions, and odds of refills in these timeframes with adjustment for fracture location, external fixator placement, and baseline patient and injury characteristics.

RESULTS

Lower extremity anatomic location and pre-operative external fixation were significantly associated with increased 1-month pre-op to 1-year post-discharge opioid filling (17.6-54.7 additional oxycodone 5-mg equivalents, all p<0.05) and number of filled prescriptions (0.28-0.54 additional prescriptions, all p<0.05). Pilon fractures and pre-operative external fixation, specifically, were associated with increased odds of two or more opioid prescriptions within the 1-month pre-op to 1-year post-discharge time frame (1.25-1.32 odds ratio, all p<0.05).

DISCUSSION

Fracture location and pre-operative external fixator placement predicted perioperative opioid demand. Articular zone (pilon, plateau, and distal femur) fracture fixation was associated with the largest increases in opioid demand after lower extremity fracture fixation. Patients with these injuries may be at highest risk of extensive opioid consumption.

Clinical use of mass spectrometry (imaging) for hard tissue analysis in abnormal fracture healing

Common traumas to the skeletal system are bone fractures and injury-related articular cartilage damage. The healing process can be impaired resulting in non-unions in 5-10% of the bone fractures and in post-traumatic osteoarthritis (PTOA) in up to 75% of the cases of cartilage damage. Despite the amount of research performed in the areas of fracture healing and cartilage repair as well as non-unions and PTOA, still, the outcome of a bone fracture or articular cartilage damage cannot be predicted. Here, we discuss known risk factors and key molecules involved in the repair process, together with the main challenges associated with the prediction of outcome of these injuries. Furthermore, we review and discuss the opportunities for mass spectrometry (MS) - an analytical tool capable of detecting a wide variety of molecules in tissues - to contribute to extending molecular understanding of impaired healing and the discovery of predictive biomarkers. Therefore, the current knowledge and challenges concerning MS imaging of bone and cartilage tissue as well as in vivo MS are discussed. Finally, we explore the possibilities of in situ, real-time MS for the prediction of outcome during surgery of bone fractures and injury-related articular cartilage damage.

Do acute inflammatory cytokines affect 3- and 12-month postoperative functional outcomes-a prospective cohort study of 12 patients with proximal tibia fractures

BACKGROUND

Patients with intra-articular fractures tend to develop post-traumatic osteoarthritis (PTOA). The initial inflammatory response with elevation of inflammatory cytokines following joint trauma might be responsible for triggering cartilage catabolism and degradation. We aimed to identify and quantify cytokine levels in fractured and healthy knee joints and the correlation of these cytokines with clinical outcomes.

METHODS

In this prospective cohort study, synovial fluid and plasma were collected from 12 patients with proximal intra-articular tibia fractures before surgery. The concentration of sixteen inflammatory cytokines, two cartilage degradation products and four metabolic mediators where measured, comparing the acute injured knee with the healthy contralateral knee. Patients were evaluated 3- and 12-months after surgery with clinical parameters and radiographical scanning. Non-parametrical Wilcoxon rank-sum and Spearman tests were used for statistical analysis, and a P-value below 0.05 was considered significant.

RESULTS

We found an elevation of the pro-inflammatory cytokines IL-1β, IL-2, IL-6, IL-8, IL-12p70, TNF-α, IFN-y, MMP-1, MMP-3, and MMP-9 and a simultaneous elevation of the anti-inflammatory cytokines IL-1RA, IL-4, IL-10, and IL-13 in the injured knee. Several pro- and anti-inflammatory cytokines and metabolic mediators were correlated with clinical outcomes 12 months after surgery, especially with pain perception.

CONCLUSIONS

Our results support that an inflammatory process occurs after intra-articular knee fractures, which is characterized by the elevation of both pro- and anti-inflammatory cytokines. There was no sign of cartilage damage within the timeframe from injury to operation. We found a correlation between the initial inflammatory reaction with clinical outcomes 12 months after surgery.

Effect of infusion irrigation with different irrigating solutions on transient receptor potential vanilloid 5 and intra-articular inflammation in a post-traumatic osteoarthritis rabbit model

BACKGROUND

The incidence of post-traumatic osteoarthritis (PTOA) after anterior cruciate ligament reconstruction (ACLR) is high, but there is still a lack of intra-operative preventive measures. This study aimed to evaluate the effect of different irrigating solutions continuous irrigation on intra-articular inflammation and cartilage degeneration.

METHODS

66 New Zealand rabbits were randomly divided into normal (N) group, no treatment (NT) group, sodium chloride (NaCl) group, magnesium sulfate (MgSO4) group, and calcium chloride (CaCl2) group. The right knee joint of the experimental group was utilized to construct the model of PTOA, and the left side was utilized as the normal control group. At different time points postoperatively, the blood concentration of hemoglobin and Mg2 + , the synovial fluid concentration of IL-1 β, TNF-α, tartrate-resistant acid phosphatase-5b (TRAP-5b), and Type II Collagen, the gene expression of IL-1 β and MMP-3, and the protein expression of TRPV5 and CaM were detected. Pearson's linear correlation was employed to identify the possible relationship between the expression of TRAP-5b and the expression of IL-1β, IL-6, TNF-α, and Type II collagen. The hematoxylin and eosin staining (HE), Masson's trichrome staining, and Alcian blue staining were performed at postoperative 35 days. Osteoarthritis Scoring (OA score) comprised categories including Alcian blue staining, cartilage histology, the cellular density of cartilage, degree of cell disintegration, and formation of chondrocyte cluster were blindly scored by trained researchers at postoperative 35 days.

RESULTS

There was no statistical difference (P > 0.05) in the hemoglobin concentration between different groups. The concentration of serum Mg2+ in the MgSO4 group was higher than that of the other three groups (P < 0.05) on the same day of operation, then gradually decreased. The expression of IL-1 β, IL-6, and TRAP-5b in synovial fluid increased 5 days after the operation, decreased at 15 days, and then increased again with time in the NT group, NaCl group, and NT group and NaCl group. At 35 days after the operation, the expression of IL-1 β, IL-6, TRAP-5b, and type II collagen in the MgSO4 group were lower than that in the other three groups (except group N) (P < 0.05).The correlation analysis results showed that the TRAP-5b levels correlated positively with IL-1 β, IL-6, TNF-α, and type II collagen concentrations. The histological examination revealed that the surface smoothness of cartilage, the morphology of chondrocytes, the arrangement of collagen fibers, and the density of proteoglycan in the MgSO4 group were better than those in other experimental groups. At 35 days postoperatively, the gene expression of IL-1 β and MMP-3 and the protein expression of CaM and TRPV5 in synovium in the MgSO4 group was lower than that in the NaCl group and CaCl2 group.

CONCLUSION

Intra-operative irrigation with magnesium sulfate solution can inhibit the inflammatory factors and the expression of TRPV5, which can also reduce collagen loss and delay cartilage degeneration. Therefore, the use of magnesium sulfate in intra-operative irrigation may be an ideal choice to prevent PTOA.

An Evidence-Based Systematic Review of Human Knee Post-Traumatic Osteoarthritis (PTOA): Timeline of Clinical Presentation and Disease Markers, Comparison of Knee Joint PTOA Models and Early Disease Implications

Understanding the causality of the post-traumatic osteoarthritis (PTOA) disease process of the knee joint is important for diagnosing early disease and developing new and effective preventions or treatments. The aim of this review was to provide detailed clinical data on inflammatory and other biomarkers obtained from patients after acute knee trauma in order to (i) present a timeline of events that occur in the acute, subacute, and chronic post-traumatic phases and in PTOA, and (ii) to identify key factors present in the synovial fluid, serum/plasma and urine, leading to PTOA of the knee in 23-50% of individuals who had acute knee trauma. In this context, we additionally discuss methods of simulating knee trauma and inflammation in in vivo, ex vivo articular cartilage explant and in vitro chondrocyte models, and answer whether these models are representative of the clinical inflammatory stages following knee trauma. Moreover, we compare the pro-inflammatory cytokine concentrations used in such models and demonstrate that, compared to concentrations in the synovial fluid after knee trauma, they are exceedingly high. We then used the Bradford Hill Framework to present evidence that TNF-α and IL-6 cytokines are causal factors, while IL-1β and IL-17 are credible factors in inducing knee PTOA disease progresssion. Lastly, we discuss beneficial infrastructure for future studies to dissect the role of local vs. systemic inflammation in PTOA progression with an emphasis on early disease.

Elevation of Inflammatory Cytokines and Proteins after Intra-Articular Ankle Fracture: A Cross-Sectional Study of 47 Ankle Fracture Patients

Introduction

Intra-articular fractures are the leading etiology for posttraumatic osteoarthritis (PTOA) in the ankle. Elevation of proinflammatory cytokines following intra-articular fracture may lead to synovial catabolism and cartilage degradation. We aimed to compare cytokine levels in injured and healthy ankle joints, examine the longer-term cytokine levels in fractured ankles, and investigate the association between cytokine levels in fractured ankles and plasma.

Materials and Methods

In this cross-sectional study, synovial fluid (SF) and plasma of forty-seven patients with acute intra-articular ankle fractures and eight patients undergoing implant removal were collected prior to surgery. We determined concentrations of sixteen inflammatory cytokines, two cartilage degradation proteins, and four metabolic proteins and compared the levels in acutely injured ankles with those of the healthy contralateral side or during metal removal. Cytokine levels in injured ankles were also compared to serum cytokine levels. Nonparametric Wilcoxon rank-sum and Spearman tests were used for statistical analysis, and a p value below 0.05 was considered significant.

Results

Compared to the healthy ankles, the synovial fluid in ankles with acute intra-articular fracture had elevated levels of several proinflammatory cytokines and proteases (IL-1β, IL-2, IL-6, IL-8, IL-12p70, TNF, IFNγ, MMP-1, MMP-3, and MMP-9) and anti-inflammatory cytokines (IL-1RA, IL-4, IL-10, and IL-13). The levels of cartilage degradation products (ACG, CTX-2) and metabolic mediators (TGF-β1 and TGF-β2) were also significantly higher. Synovial concentrations of ACG, IL-12-p70, IFNγ, IL-4, and bFGF correlated with serum levels. While most of the examined synovial cytokines were unchanged after implant removal, IL-4 and IL-6 levels were upregulated.

Conclusions

We show that an acute ankle fracture is followed by an inflammatory reaction and cartilage degeneration. These data contribute to the current understanding of the protein regulation behind the development of PTOA and is a further step towards supplementing the current surgical treatment. This cross-sectional study was "retrospectively registered" on the 31th October 2017 at ClinicalTrials.gov (NCT03769909). The registration was carried out after inclusion of the first patient and prior to finalization of patient recruitment and statistical analyses: https://clinicaltrials.gov/ct2/show/NCT03769909?term=NCT03769909&draw=2&rank=1.

Long-term outcomes after different types of Horne and Tanzer olecranon fractures

BACKGROUND

It is unclear whether the outcomes differ after different Horne and Tanzer types of olecranon fractures.

MATERIALS AND METHODS

We evaluated 40 men and 55 women with isolated olecranon fractures, journals and radiographs from fracture event. The fractures were classified according to Horne and Tanzer. After a mean 19 years after the fracture events, we evaluated subjective, clinical and radiographic outcomes, using the uninjured arms as controls.

RESULTS

95% of patients with type I fractures reported, at follow-up, no differences between the elbows, 80% with type II fractures and 95% with type III fractures (p = 0.43). The three types of fractures had no differences in elbow range of motion or hand grip strength (when comparing injured and uninjured arms) and the proportions of individuals with radiographic elbow degenerative changes or joint space reduction were no different (all p > 0.05). Individuals with elbow degenerative changes had no inferior subjective elbow function compared to individuals with normal radiographs (p = 0.66), in contrast to those with joint space reduction compared to individuals with normal radiographs (p < 0.001).

INTERPRETATION

All types of Horne and Tanzer olecranon fractures have favourable long-term outcome. Elbow joint space reduction is associated with inferior subjective elbow function while degenerative changes are not.

A VCP modulator, KUS121, as a promising therapeutic agent for post-traumatic osteoarthritis

Post-traumatic osteoarthritis (PTOA) is a major cause which hinders patients from the recovery after intra-articular injuries or surgeries. Currently, no effective treatment is available. In this study, we showed that inhibition of the acute stage chondrocyte death is a promising strategy to mitigate the development of PTOA. Namely, we examined efficacies of Kyoto University Substance (KUS) 121, a valosin-containing protein modulator, for PTOA as well as its therapeutic mechanisms. In vivo, in a rat PTOA model by cyclic compressive loading, intra-articular treatments of KUS121 significantly improved the modified Mankin scores and reduced damaged-cartilage volumes, as compared to vehicle treatment. Moreover, KUS121 markedly reduced the numbers of TUNEL-, CHOP-, MMP-13-, and ADAMTS-5-positive chondrocytes in the damaged knees. In vitro, KUS121 rescued human articular chondrocytes from tunicamycin-induced cell death, in both monolayer culture and cartilage explants. It also significantly downregulated the protein or gene expression of ER stress markers, proinflammatory cytokines, and extracellular-matrix-degrading enzymes induced by tunicamycin or IL-1β. Collectively, these results demonstrated that KUS121 protected chondrocytes from cell death through the inhibition of excessive ER stress. Therefore, KUS121 would be a new, promising therapeutic agent with a protective effect on the progression of PTOA.

Computed Tomographic Measurement of Trochlear Depth in Three Breeds of Brachycephalic Dog

OBJECTIVE

 The aim of this study was to determine the trochlear sulcus depth of three common brachycephalic breeds at risk of medial patellar luxation.

STUDY DESIGN

 Retrospective blinded clinical study using a previously validated ratio (T/P) of maximal trochlear sulcus depth (T) and maximal patellar craniocaudal thickness (P) measured on computed tomography, to assess trochlear sulcus depth in Pugs, French Bulldogs and English Bulldogs without clinical patellar luxation. The effect of breed on T/P was assessed using one-way linear regression models.

RESULTS

 The mean T/P was affected by breed (p < 0.001). There was significant difference between Pugs (0.45) and French Bulldogs (0.38) and between Pugs and English Bulldogs (0.4). There was no significant difference between Pugs and previously published data for non-brachycephalic and mixed breed dogs (0.46) (p = 0.39). Mean T/P was significantly reduced in the brachycephalic dog breeds combined compared with the previously published data (p < 0.001).

CONCLUSION

 The trochlear sulcus varies by breed and was more shallow in French and English Bulldogs than Pugs, hence a shallow sulcus may be a breed-driven characteristic. The three breeds assessed are at risk of patellar luxation but sulcus depth did not directly correlate with previously published risk factors-the contribution of sulcus depth to the aetiopathogenesis of patellar luxation remains unclear. Trochlear recession to achieve patellar coverage of 50% may be excessive considering maximal breed normal depth.

The role of concomitant ligament injury in the development of post-traumatic osteoarthritis after distal radius fractures: a protocol for a systematic review

INTRODUCTION

Treatment of distal radius fractures (DRFs) aims to restore anatomic position of the fracture fragments and congruity of the articular surface to optimise functional outcomes and prevent osteoarthritis in the long term. While ligament injury of the wrist is often associated with DRFs and sole ligament injuries of the wrist lead to osteoarthritis, it is plausible that concomitant ligament injury in DRFs may aggravate degenerative changes of the wrist. The relationship between concomitant ligament injury and post-traumatic osteoarthritis in patients with DRFs is unclear. This study aims to identify the types of associated ligament injury in patients with a DRF and to elucidate the association of ligament injury on the development of post-traumatic osteoarthritis.

METHODS AND ANALYSIS

This protocol is written in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol (PRISMA-P) guidelines. An electronic search in MEDLINE, Embase, Web of Science, Cochrane Central Register of Trials and Google Scholar has been created and performed by a Health Sciences librarian with expertise in systematic review searching. Original research articles in English literature, which report on concomitant ligament injury of the wrist in relation to post-traumatic osteoarthritis, patient-reported outcome measures or clinician-reported outcome measures in patients (aged ≥18 years) with DRFs will be included. Two reviewers will independently screen and appraise articles and perform data extraction. In case of any disagreements, a third reviewer will be consulted. A systematic qualitative synthesis will be performed using text and tables.

ETHICS AND DISSEMINATION

No ethical approval is required, since this is a protocol for a systematic review. The systematic review will be submitted for publication in a peer-reviewed scientific journal and for presentation at relevant conferences.

PROSPERO REGISTRATION NUMBER

CRD42020165007.

Correlation of 3D Joint Space Width From Weightbearing CT With Outcomes After Intra-articular Calcaneal Fracture

BACKGROUND

Posttraumatic osteoarthritis (PTOA) of the subtalar joint is a serious, disabling, and frequent complication following intra-articular calcaneal fractures (IACFs). Using plain radiographs to assess the subtalar joint for PTOA is imprecise and insensitive, hindering progress toward improving treatment and assessing outcomes. This study explored how low-dose weightbearing computed tomography (WBCT) can be used to provide reliable, quantitative 3D measures of subtalar joint space width (JSW) following IACF and correlated the 3D JSW with clinical outcomes.

METHODS

After institutional review board approval, 21 patients (15 male; age, 28-70 years) who sustained IACFs and were treated with percutaneous surgical reduction underwent WBCT scans at follow-up visits 2 to 15 years (average, 7.8 years) after surgical treatment. Subtalar joint 3D JSW was computed after a semiautomated protocol was used to segment the talus and calcaneus from the WBCT data. Mean and minimum 3D JSW measurements were calculated and compared with Kellgren-Lawrence (KL) radiographic osteoarthritis grade, RAND-36 Physical (PCS) and Mental (MCS) Component Scores, and visual analog scale (VAS) pain scores. Spearman's rank correlation was used to detect the strength of association between variables, with significance set at P < .05.

RESULTS

Mean 3D JSW values measured from WBCT for patients with IACFs ranged from 0.9 to 2.5 mm (1.7 ± 0.4 mm) over the entire subtalar joint. Intra- and interrater reliabilities for the WBCT-based JSW measurement technique were 0.95 (95% CI, 0.91-0.97) and 0.97 (95% CI, 0.95-0.98), respectively. Mean and minimum 3D JSW values correlated inversely with VAS pain scores and KL grade (P < .05), particularly in central and posterior subtalar regions.

CONCLUSION

WBCT-based methods were used to quantify the preservation/loss of JSW in patients with IACFs, enabling more accurate, definitive measurement of subtalar PTOA. The results of this study demonstrate that WBCT can be utilized to objectively assess subtalar PTOA and help us to better understand how arthritic changes affect actual patient experience.

LEVEL OF EVIDENCE

Level III, prognostic comparative study.

Articular reductions - how close is close enough? A narrative review

Intra-articular fractures are a unique subset of fractures as they involve a varying extent of damage to cartilage. The impact of this articular fracture causes significant microscopic and macroscopic changes, as well as biomechanical irregularities, which can lead to further cartilage damage, and ultimately cascade down the dreaded path to arthritis. It is generally believed that an anatomic reduction of an articular fracture is the necessary goal of treatment for these injuries, however it yet to be delineated how perfect this reduction has to be. A comprehensive literature review was carried out to create a best available evidence guide to the acceptability of upper extremity and lower extremity articular fracture reductions. Ultimately, a perfect anatomic reduction is the best strategy to minimize abnormal loading and wear patterns, however this should be balanced with the realistic factors of each individual case, such as the level of difficulty, joint involved, surgical timing, and patient activity levels.