Nathan A Huebschmann, Jonathan L Katzman, Joseph X Robin, Morteza Meftah, Joshua C Rozell, Ran Schwarzkopf
{"title":"Ratio of Weight-to-Tibial Baseplate Surface Area in Predicting Aseptic Tibial Loosening in TKA and the Protective Effect of Tibial Stem Extensions.","authors":"Nathan A Huebschmann, Jonathan L Katzman, Joseph X Robin, Morteza Meftah, Joshua C Rozell, Ran Schwarzkopf","doi":"10.2106/JBJS.24.01226","DOIUrl":"https://doi.org/10.2106/JBJS.24.01226","url":null,"abstract":"<p><strong>Background: </strong>High body mass index (BMI) is a risk factor for tibial baseplate loosening following total knee arthroplasty (TKA) but may not adequately correlate with stresses at the tibial baseplate. In this study, we aimed to determine an optimal cutoff of a weight-to-tibial baseplate surface-area ratio (weight/SA) for predicting aseptic tibial baseplate loosening. We further examined whether tibial stem extensions have a protective effect.</p><p><strong>Methods: </strong>We identified 16,368 patients who underwent primary, elective TKA from June 2011 to March 2023. Patient demographics, including age, sex, and race, implants used, and revision surgeries were extracted. Revisions were manually reviewed to confirm revision indications. The exact surface areas of tibial baseplates were obtained from manufacturers. Receiver operating characteristic (ROC) analysis of patients without tibial stem extensions was utilized to examine the utility of BMI and weight/SA for predicting aseptic tibial baseplate loosening. Optimal weight/SA and BMI cutoffs for predicting loosening were determined. The effect of tibial stem extensions on loosening was then examined in patients at or above (n = 7,698; 3.7% with stem extension) and below (n = 8,670; 1.3% with stem extension) the determined weight/SA cutoff.</p><p><strong>Results: </strong>There were 16,368 patients in the final sample (median age, 67 years; 68.9% female; 54.1% White). Weight/SA (area under the curve [AUC] = 0.653; p < 0.001) was a better predictor of aseptic tibial baseplate loosening requiring revision compared with patient BMI (AUC = 0.624; p < 0.001). The optimal weight/SA cutoff for predicting loosening was 0.0162 kg/mm2 (sensitivity = 0.747, specificity = 0.537). Multivariable logistic regression demonstrated that being at or above the weight/SA cutoff (odds ratio [OR] = 3.17; p < 0.001) but not the BMI cutoff (p = 0.911) was a significant predictor of revision for tibial baseplate loosening in patients without stem extensions. No cases of revision for aseptic tibial baseplate loosening in patients with stem extensions occurred either at or above or below the cutoff. The rate of revision for aseptic tibial baseplate loosening in patients without stem extensions was 0.3% for patients below and 1.0% for patients at or above the weight/SA cutoff.</p><p><strong>Conclusions: </strong>The ratio of weight-to-tibial baseplate surface area was more predictive of revision for aseptic tibial baseplate loosening following TKA compared with BMI alone. For patients with obesity with small tibial baseplate sizes, utilization of a tibial stem extension may protect against tibial loosening.</p><p><strong>Level of evidence: </strong>Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.</p>","PeriodicalId":15273,"journal":{"name":"Journal of Bone and Joint Surgery, American Volume","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143784370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pooria Salari, Garrett W D Easson, Kaitlyn S Broz, Michael P Kelly, Simon Y Tang
{"title":"Effects of Sustained Tensile Distraction on Vertebrae and Intervertebral Disc Growth: An in Vivo Study Using a Mouse Tail Model.","authors":"Pooria Salari, Garrett W D Easson, Kaitlyn S Broz, Michael P Kelly, Simon Y Tang","doi":"10.2106/JBJS.24.00224","DOIUrl":"https://doi.org/10.2106/JBJS.24.00224","url":null,"abstract":"<p><strong>Background: </strong>Directed growth modulation is commonly utilized as a surgical treatment for early-onset scoliosis. Growing rods are instrumented on the spine and apply sustained tension on the immature spine for a substantial amount of time, with the clinical goal of accommodating axial expansion of the spine. Despite the use of growing rods in humans, the mechanobiology of the spinal tissues under tensile loading remains relatively unknown. To bridge this knowledge gap, we developed a preclinical mouse model that allows for mechanistic investigations of sustained tension on the spine.</p><p><strong>Methods: </strong>Using custom 3D-printed washers and tunable springs, we distracted across the seventh and ninth caudal vertebrae of adolescent and young adult C57BL/6 female mice with forces that were approximately 2 times the body mass of the animal. The springs were replaced weekly to maintain tension for the duration of the experiment. A set of 6-week-old animals were first instrumented for 10 weeks to evaluate the feasibility and tolerability. Subsequently, the 6- and 12-week-old experimental animals were instrumented until they were 20 weeks of age in order to evaluate the effects of tension until adulthood. The spines were monitored using digital radiography and micro-computed tomography (µCT), and the intervertebral discs (IVDs) were evaluated using mechanical testing and compositional assays.</p><p><strong>Results: </strong>The device was well tolerated and caused no notable complications. The tensile forces lengthened the vertebrae in the 6-week-old animals that were instrumented for 14 weeks and in the 12-week-old animals that were instrumented for 8 weeks. Increased IVD heights were observed in the 6-week-old animals but not in the 12-week-old animals. The porosity of the vertebral end plates increased following instrumentation in all groups but progressively recovered over time.</p><p><strong>Conclusions: </strong>Distraction accelerated the lengthening of the vertebrae and the heightening of the IVD, with no observable degeneration or decline in the mechanical performance of the IVDs for these distraction conditions.</p><p><strong>Clinical relevance: </strong>This model will be useful for investigating how spinal tissues adapt to directed growth modulation with maturation and aging.</p>","PeriodicalId":15273,"journal":{"name":"Journal of Bone and Joint Surgery, American Volume","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143780219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Emma-Sofia Luoto, Jenni Jalkanen, Ilari Kuitunen, Reijo Sund, Yrjänä Nietosvaara
{"title":"Universal Clinical DDH Screening Complemented with Targeted Ultrasound Is Effective in Finland.","authors":"Emma-Sofia Luoto, Jenni Jalkanen, Ilari Kuitunen, Reijo Sund, Yrjänä Nietosvaara","doi":"10.2106/JBJS.24.00313","DOIUrl":"10.2106/JBJS.24.00313","url":null,"abstract":"<p><strong>Background: </strong>The late diagnosis rate of developmental dysplasia of the hip (DDH) with universal ultrasound screening is 0.2 per 1,000 children according to a recent meta-analysis, which is the same as in Japan where selective ultrasound screening is used. We hypothesized that Finland's current program of universal clinical screening complemented with targeted ultrasound is noninferior to universal and selective ultrasound screening programs.</p><p><strong>Methods: </strong>For this retrospective cohort study, we collected the number of children <15 years of age who were diagnosed with DDH (International Classification of Diseases, Tenth Revision [ICD-10] codes Q65.0-Q65.6 and Ninth Revision [ICD-9] code 7543) as their primary diagnosis after ≥3 visits to a physician. These data were obtained from the Finnish Care Register for Health Care, which collects the ICD-10 and ICD-9 codes from every medical appointment. We calculated the annual incidence of DDH diagnoses per 1,000 newborns between 2002 and 2021. Late diagnosis of DDH was defined as a finding of DDH in children aged 6 months through <15 years at the initial diagnosis who had undergone treatment under anesthesia (closed reduction and casting or surgery). We also registered the geographic, age, and sex distributions of the DDH diagnoses.</p><p><strong>Results: </strong>During the 20-year study period, 1,103,269 babies were born (median per year, 57,214 babies; range per year, 45,346 to 60,694 babies). A total of 6,421 children had a diagnosis of DDH (mean per year, 321 children; range per year, 193 to 405 children), with a mean calculated incidence of 5.8 per 1,000 newborns (95% confidence interval [CI], 5.7 to 6.0). Altogether, 120 children aged 6 months through <15 years were treated for DDH, with little annual variation (median, 6.5 children; range, 2 to 9 children). The mean national incidence of late-diagnosed cases was 0.11 per 1,000 newborns (95% CI, 0.09 to 0.13).</p><p><strong>Conclusions: </strong>Finland's current DDH screening program, which includes universal clinical screening with targeted ultrasound, is noninferior when compared with other screening programs.</p><p><strong>Level of evidence: </strong>Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.</p>","PeriodicalId":15273,"journal":{"name":"Journal of Bone and Joint Surgery, American Volume","volume":" ","pages":"e26"},"PeriodicalIF":4.4,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11949211/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143468040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Akbar N Syed, David Isaacs, Leta Ashebo, Divya Talwar, Jason B Anari, J Todd R Lawrence
{"title":"Nerve Recovery in Pediatric Supracondylar Humeral Fractures: Assessing the Impact of Time to Surgery.","authors":"Akbar N Syed, David Isaacs, Leta Ashebo, Divya Talwar, Jason B Anari, J Todd R Lawrence","doi":"10.2106/JBJS.24.00371","DOIUrl":"10.2106/JBJS.24.00371","url":null,"abstract":"<p><strong>Background: </strong>Nerve injuries in pediatric supracondylar humeral (SCH) fractures occur in 2% to 35% of patients. Previous research has suggested that isolated anterior interosseous nerve injuries are not influenced by the time to surgery; however, little is known about other nerve injuries or mixed, motor, and sensory injuries. With this study, we aimed to examine the impact of time to surgery on nerve recovery in patients with traumatic nerve injuries associated with SCH fractures.</p><p><strong>Methods: </strong>Patients <18 years of age with SCH fractures stabilized using percutaneous pins during the period of January 2009 to June 2022 were retrospectively reviewed. Patients presenting with any traumatic nerve injury noted preoperatively were included, while those with iatrogenic or postoperative nerve injuries and incomplete documentation were excluded. Demographic data, injury characteristics, time to surgery, and number of days to nerve recovery were collected. Comparisons of nerve recovery time by anatomic distribution and functional deficit using an 8-hour time-to-surgery cutoff were made in bivariate and multivariate analyses.</p><p><strong>Results: </strong>A total of 2,753 patients with SCH fractures were identified, with 214 of the patients having an associated nerve injury. Documentation of nerve recovery was available for 197 patients (180 patients with complete recovery) with an overall mean age of 6.8 ± 2.1 years. Time to recovery differed significantly when comparing the motor, sensory, and mixed-deficit cohorts (p < 0.001). Early surgery (≤8 hours from injury to surgery) was significantly associated with shorter overall time to nerve recovery (p = 0.002), recovery of multiple nerve distributions (p = 0.011), and recovery of mixed motor and sensory deficits (p = 0.007). On multivariable analysis, mixed nerve deficits (hazard ratio [HR], 0.537 [95% CI, 0.396 to 0.728]; p < 0.001) and time from injury to treatment of >8 hours (HR, 0.542 [95% CI, 0.373 to 0.786]; p = 0.001) were significantly associated with delayed nerve recovery.</p><p><strong>Conclusions: </strong>Surgical timing impacts the time to recovery of complex nerve injuries. Early surgical management of patients with mixed motor-sensory deficits may help to reduce the time to complete nerve recovery.</p><p><strong>Level of evidence: </strong>Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.</p>","PeriodicalId":15273,"journal":{"name":"Journal of Bone and Joint Surgery, American Volume","volume":" ","pages":"687-693"},"PeriodicalIF":4.4,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143468045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Direction of the Future: Opioid-Free Protocols: Commentary on an article by Robby Turk, MD, MBA, et al.: \"An Opioid-Free Perioperative Pain Protocol Is Noninferior to Opioid-Containing Management. A Randomized Controlled Trial\".","authors":"Suzanne Novak","doi":"10.2106/JBJS.24.01171","DOIUrl":"https://doi.org/10.2106/JBJS.24.01171","url":null,"abstract":"","PeriodicalId":15273,"journal":{"name":"Journal of Bone and Joint Surgery, American Volume","volume":"107 7","pages":"e28"},"PeriodicalIF":4.4,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143763460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Thessaly Graft Index: An Artificial Intelligence-Based Index for the Assessment of Graft Integrity in ACL-Reconstructed Knees.","authors":"Georgios Chalatsis, Athanasios Siouras, Vasileios Mitrousias, Ilias Chantes, Serafeim Moustakidis, Dimitris Tsaopoulos, Marianna Vlychou, Sotiris Tasoulis, Michael Hantes","doi":"10.2106/JBJS.24.00427","DOIUrl":"10.2106/JBJS.24.00427","url":null,"abstract":"<p><strong>Background: </strong>Magnetic resonance imaging (MRI) has proven to be a valuable noninvasive tool to evaluate graft integrity after anterior cruciate ligament (ACL) reconstruction. However, MRI protocols and interpretation methodologies are quite diverse, preventing comparisons of signal intensity across subsequent scans and independent investigations. The purpose of this study was to create an artificial intelligence (AI)-based index (Thessaly Graft Index [TGI]) for the evaluation of graft integrity following ACL reconstruction.</p><p><strong>Methods: </strong>The cohort study included 24 patients with an isolated ACL injury that had been treated with a hamstring tendon autograft and followed for 1 year. MRI was performed preoperatively and 1 year postoperatively. The clinical and functional evaluations were performed with use of the KT-1000 and with the following patient-reported outcome measures (PROMs): the Knee Injury and Osteoarthritis Outcome Score (KOOS), the International Knee Documentation Committee Subjective Knee Function form (IKDC), the Lysholm score, and the Tegner Activity Scale (TAS). An AI model, based on the YOLOv5 Nano version, was designed to compute the probability of accurately detecting, in the sagittal plane, a healthy ACL (on a percentage scale) and was trained on healthy and injured knees from the KneeMRI dataset. The model was used to assess the integrity of ACL grafts, with a maximum score of 100. The results were compared with the MRI assessment from an independent radiologist and were correlated with PROMs and KT-1000 laxity.</p><p><strong>Results: </strong>The mean preoperative and postoperative TGI scores were 64.21 ± 8.96 and 82.37 ± 3.53, respectively. A mean increase of 15% in the TGI scores was observed between preoperative and postoperative images. The minimum threshold for TGI to categorize a graft as healthy on the postoperative MRI was 79.21%. Twenty-two grafts were characterized as intact and 2 as reruptured, with postoperative TGI scores of 71% and 42%. The radiologist's assessment was in total agreement with the TGI scores. The correlation of the TGI ranged from moderate to good with the TAS (0.668), IKDC (0.516), Lysholm (0.521), KOOS total (0.594), and KT-1000 (0.561).</p><p><strong>Conclusions: </strong>The TGI is an AI tool that is able to accurately recognize an ACL graft rupture. Moreover, the TGI correlated with the KT-1000 postoperative values and PROM scores.</p><p><strong>Level of evidence: </strong>Diagnostic Level IV . See Instructions for Authors for a complete description of levels of evidence.</p>","PeriodicalId":15273,"journal":{"name":"Journal of Bone and Joint Surgery, American Volume","volume":" ","pages":"733-740"},"PeriodicalIF":4.4,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143370739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Robby Turk, Benjamin Averkamp, Kayla Hietpas, Caleb Michalek, Daniel Leas, Susan M Odum, Nady Hamid
{"title":"An Opioid-Free Perioperative Pain Protocol Is Noninferior to Opioid-Containing Management: A Randomized Controlled Trial.","authors":"Robby Turk, Benjamin Averkamp, Kayla Hietpas, Caleb Michalek, Daniel Leas, Susan M Odum, Nady Hamid","doi":"10.2106/JBJS.24.00460","DOIUrl":"10.2106/JBJS.24.00460","url":null,"abstract":"<p><strong>Background: </strong>In recent years, orthopaedic surgeons have attempted to decrease opioid consumption through multimodal pain management. However, a limited effort has been made to eliminate opioids entirely in the perioperative period. The purpose of this study was to compare the efficacy and safety of a novel opioid-free pain management pathway with that of an opioid-containing pathway across 5 common orthopaedic subspecialty surgical procedures.</p><p><strong>Methods: </strong>In a 1:1, unblinded fashion, 315 patients were randomized to a perioperative pain management pathway that was either opioid-free (n = 157) or opioid-containing (n = 158). Pain was measured with a numeric rating scale (NRS) for pain of 0 to 10 at 6 hours, 12 hours, 24 hours (the primary outcome assessing noninferiority), 2 weeks, 6 weeks, and 1 year after the surgical procedure. Data on patient characteristics, deviations from the pain management pathway, morphine milligram equivalents (MME), readmissions, adverse events, and patient-reported outcomes were collected.</p><p><strong>Results: </strong>There were 315 patients in the final group, with a mean age of 63.6 years. Of the patients in the study, 59.7% were female, 85.7% were White, 12.4% were Black/African-American, 1.0% were Hispanic/Latino, 0.6% were American Indian, and 0.3% were unknown. At 24 hours, the median NRS for pain in the opioid-free group (2 [interquartile range (IQR), 0 to 4]) was statistically noninferior (p < 0.0001) to the opioid-containing group (4 [IQR, 2 to 6]). Pain levels were significantly lower in the opioid-free group than in the opioid-containing group at 12 hours (p = 0.0173) and 2 weeks (p = 0.0003). Pain scores at 6 hours, 6 weeks, and 1 year were similar. Patients in the opioid-free group reported significantly greater comfort at 24 hours (p = 0.0392) and higher satisfaction with pain control (p = 0.0355) at 6 weeks. There were no reported adverse events or unplanned readmissions. Demographic characteristics were similar between the 2 groups.</p><p><strong>Conclusions: </strong>Across 5 common orthopaedic subspecialty procedures, an opioid-free pain management pathway was safe and effective and provided noninferior pain control at 24 hours compared with the opioid-containing pathway.</p><p><strong>Level of evidence: </strong>Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.</p>","PeriodicalId":15273,"journal":{"name":"Journal of Bone and Joint Surgery, American Volume","volume":" ","pages":"665-677"},"PeriodicalIF":4.4,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143390922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Can We Improve the Results of Internal Fixation?: Commentary on an article by Boris C. Wagner, BMedSci(Hons), MBChB, et al.: \"Outcomes for Younger Patients with Femoral Neck Fractures\".","authors":"Gerard Slobogean","doi":"10.2106/JBJS.25.00033","DOIUrl":"https://doi.org/10.2106/JBJS.25.00033","url":null,"abstract":"","PeriodicalId":15273,"journal":{"name":"Journal of Bone and Joint Surgery, American Volume","volume":"107 7","pages":"e29"},"PeriodicalIF":4.4,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143763417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Transformative Impact and Persisting Challenges of Intramedullary Nailing in Low- and Middle-Income Countries: Commentary on an article by Aditya Subramanian, et al.: \"Delayed Surgery Increases the Rate of Infection in Closed Diaphyseal Tibial and Femoral Fractures\".","authors":"Kiran J Agarwal-Harding","doi":"10.2106/JBJS.24.01282","DOIUrl":"https://doi.org/10.2106/JBJS.24.01282","url":null,"abstract":"","PeriodicalId":15273,"journal":{"name":"Journal of Bone and Joint Surgery, American Volume","volume":"107 7","pages":"e31"},"PeriodicalIF":4.4,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143763637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ernesto S Quinto, Nathan P Reyes, Joshua P Steimel, JuEun Lee, John M Dowbak
{"title":"Properties of Tungsten Carbide Rings When Compressed to Failure or Cut with a Diamond Grinding Bit: A Biomechanical Study.","authors":"Ernesto S Quinto, Nathan P Reyes, Joshua P Steimel, JuEun Lee, John M Dowbak","doi":"10.2106/JBJS.24.00582","DOIUrl":"10.2106/JBJS.24.00582","url":null,"abstract":"<p><strong>Background: </strong>Tungsten carbide rings are increasingly popular modern jewelry items. Tungsten carbide is an extremely dense, hard metal. Previously described methods to remove tungsten carbide rings include using locking pliers to compress the ring or cutting the ring with a high-speed dental drill.</p><p><strong>Methods: </strong>A universal mechanical testing system (MTS) machine was used to diametrically compress tungsten carbide rings 9 mm in length and 2.4 mm in thickness with a 23.4-mm outer diameter and a 21.0-mm inner diameter while measuring the force required to fracture the rings. A computer numerical control (CNC) machine was used to cut tungsten carbide rings with a diamond grinding bit with and without a flow of normal saline solution. An infrared thermal camera was used to record the temperature at the site of contact between the ring and the grinding bit and at a site one-quarter of the circumference along the ring.</p><p><strong>Results: </strong>A mean force with 95% confidence interval of 3.7 ± 1.2 kN was required to fracture the tungsten carbide rings via diametral compression (p = 0.05). The rings failed at a mean displacement with 95% confidence interval of 0.32 ± 0.13 mm (p = 0.05). The maximum temperature observed at the site of contact between the ring and grinding bit averaged 160.2°C including cases with and without coolant. The time to reach maximum temperature and the duration of maximum temperature differed significantly between the cases with and without coolant (p = 0.0007 and p = 0.0108, respectively).</p><p><strong>Conclusions: </strong>Tungsten carbide rings fractured with minimal displacement using a small amount of force via diametral compression. The brittle fracture pattern of the rings produced minimal comminution. Tungsten carbide rings reached extreme temperatures when cut with a high-speed diamond grinding bit despite cooling with normal saline solution.</p><p><strong>Clinical relevance: </strong>Previously documented methods to remove a tungsten carbide ring include breaking the ring by compressing it with pliers or cutting it off with a high-speed dental drill. Clinicians should be aware of potential complications of current methods to remove tungsten carbide rings.</p>","PeriodicalId":15273,"journal":{"name":"Journal of Bone and Joint Surgery, American Volume","volume":" ","pages":"e27"},"PeriodicalIF":4.4,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11949206/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143416797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}