Perioperative Complications and Radiographic Outcomes Following Cervical Laminoplasty: A Review of 105 Cases from a Single Academic Center.

OBJECTIVE: To assess complications and to compare preoperative and postoperative radiographic measures in patients who underwent cervical laminoplasty. METHODS: We evaluated patients undergoing cervical laminoplasty between 2011 and 2022 at an academic medical center. Patient demographics, intraoperative and postoperative complications, and preoperative and postoperative radiographic parameters were recorded. RESULTS: Of 150 patients undergoing cervical laminoplasty during 2011-2022, 105 met the inclusion criteria. We identified 22 (21.0%) adverse events in 20 patients: 4 intraoperative (3.8%), 10 perioperative (9.5%), and 8 delayed postoperative (7.6%). Among adverse events, 13 (12.4%) were judged to be minor and 9 (8.6%) were judged to be major complications. Revision surgery was required in 6 (5.7%) patients. Both preoperative and postoperative cervical spine radiographic imaging was available in 47 (44.8%) of the 105 patients. Mean preoperative and postoperative C2-7 Cobb angles were 14.7° and 12.3°, respectively (P = 0.04). Mean preoperative and postoperative sagittal vertical axis measurements were 29.2 mm and 33.3 mm, respectively (P = 0.07). Mean preoperative and postoperative T1 slopes were 32.3° and 30.2°, respectively (P = 0.07). CONCLUSIONS: Cervical laminoplasty carries a significant risk of adverse events, the majority of which are minor, and has a low rate of reoperation (5.7%). The procedure does not result in significant changes in sagittal vertical axis or T1 slope. Cervical laminoplasty remains a valuable surgical option for selected patients with cervical myelopathy.

Using MaxDiff Analysis to Elicit Patients' Treatment Preferences for Distal Radius Fractures in Patients Aged 60 Years and Older.

PURPOSE: The objective of our study was to determine how the attributes of surgical and nonsurgical distal radius fracture (DRF) treatments affect patient treatment preferences. METHODS: Two hundred fifty patients aged 60 years and older were contacted from a single-hand surgeon's practice, and 172 chose to participate. We built a series of best-worst scaling experiments for the MaxDiff analysis to determine the relative importance of treatment attributes. Hierarchical Bayes analysis was used to generate individual-level item scores (ISs) for each attribute that together have a total sum of 100. RESULTS: One hundred general hand clinic patients without a history of a DRF and 43 patients with a history of a DRF completed the survey. For the general hand clinic patients, the most important attributes to avoid when choosing a DRF treatment (in descending order) were the longer time to full recovery (IS, 24.9; 95% confidence interval [CI]: 23.4-26.3), longer time spent in a cast (IS, 22.8; 95% CI, 21.5-24.2), and higher complication rates (IS, 18.4; 95% CI, 16.9-19.8). Meanwhile, for patients with a history of a DRF, the most important attributes to avoid (in descending order) were a longer time to full recovery (IS, 25.6; 95% CI, 23.3-27.9), longer time spent in a cast (IS, 22.8; 95% CI, 19.9-25.7), and abnormal alignment of the radius on x-ray (IS, 18.3; 95% CI, 15.4-21.3). For both the groups, the least concerning attributes based on the IS were appearance-scar, appearance-bump, and the need for anesthesia. CONCLUSIONS: Eliciting patient preferences is a vital component of shared decision-making and advancing patient-centered care. As conceptualized in this MaxDiff analysis, when choosing a DRF treatment, patients mostly want to avoid a longer time to full recovery and a longer time in a cast, whereas patients have the least concern about appearance and need for anesthesia. CLINICAL RELEVANCE: Eliciting patient preferences is a vital component of shared decision-making. Our results may provide guidance to surgeons in discussions on the relative benefits of surgical and nonsurgical DRF treatments, by quantifying the most and least important factors to patients.

Evaluation of PROMIS Outcomes for Surgical Treatment of Cubital Tunnel Syndrome With and Without Carpal Tunnel Syndrome.

BACKGROUND: Assessment of outcomes for cubital tunnel syndrome (CuTS) surgeries has been difficult due to heterogeneity in outcome reporting. Our objective was to evaluate the outcomes for 2 cohorts treated surgically for isolated CuTS and for combined CuTS and carpal tunnel syndrome (CTS) using Patient Reported Outcomes Measurement Information System (PROMIS). METHODS: There were 29 patients in the isolated CuTS cohort and 30 patients in the combined CuTS and CTS cohort. PROMIS Physical Function (PF), Pain Interference (PI), Depression, and Upper Extremity (UE) were completed preoperatively and 1-week, 6-weeks, and 3-months postoperatively. Responsiveness was evaluated by standardized response means (SRM). RESULTS: Significant improvements from the 1-week to 6-week postoperative period are shown in the isolated CuTS cohort for PROMIS PF (P = .002), PI (P = .0002), and UE (P = .02), but scores plateau after 6-weeks postoperatively. A similar pattern for the same time points was seen for the combined CuTS and CTS group for PROMIS PF (P = .001), PI (P = .02), and UE (P = .04), with a plateau of scores beyond 6 weeks postoperatively. PROMIS UE was more responsive (SRM range: 0.11-1.03) than the PF (SRM range: 0.02-0.52) and PI (SRM range: 0.11-0.40), which were both mildly responsive for both cohorts. CONCLUSIONS: PROMIS lacks the sensitivity to show improvement beyond 6-weeks postoperatively for both isolated CuTS and combined CuTS and CTS. Patients with combined nerve compressions follow similar trajectories in the postoperative period as those with isolated CuTS. LEVEL OF EVIDENCE: Level IV.

Responsiveness of PROMIS Instruments for Trigger Digit After Corticosteroid Injection or A1 Pulley Release.

PURPOSE: The purpose of the study was to determine if the patient-reported outcomes measurement information system (PROMIS) is sufficiently sensitive to detect improvement after 2 common treatments of trigger finger: corticosteroid injection or A1 pulley release. METHODS: This retrospective cohort study included 72 patients in the injection group and 51 in the A1 pulley release group. PROMIS physical function (PF), pain interference (PI), and upper extremity (UE) scores were collected at baseline and 6 weeks after injection for the injection group and at baseline, and 1 week, 6 weeks, and 3 months after surgery for A1 pulley release patients. Descriptive statistics and paired t tests were used to compare PROMIS scores within each cohort. Standardized response means (SRMs) were calculated for each PROMIS domain to gauge instrument responsiveness. RESULTS: Average age was 62 years, 65% were female patients, and 86% were White for the steroid injection cohort, compared to 60 years, 71%, and 88%, respectively, for the A1 pulley release cohort. For the steroid injection group, mean PROMIS PI scores (-4.0 points; SRM = -0.6) and PROMIS UE scores (+3.3 points; SRM = 0.5) improved significantly at 6 weeks after injection compared to baseline. Meanwhile, A1 pulley release patients improved significantly in mean PI scores (-3.7 points; SRM = -0.5) and in UE scores (+4.9 points; SRM = 0.7) at 3 months after surgery compared to baseline. CONCLUSIONS: Clinical improvements after trigger digit treatments are reflected in improved PROMIS PI and UE scores that reach previously accepted minimum clinically important difference values for hand patients. PROMIS PI and UE also are more responsive than PROMIS PF in capturing improvement for trigger digit treatments. CLINICAL RELEVANCE: As health care payers continue to emphasize patient-reported outcomes to determine treatment value and set reimbursement rates, this study helps establish that clinical improvement after trigger digit treatments are reflected in PROMIS PI and UE domains by reaching previously established minimum clinically important difference values for hand patients.

Evaluation of PROMIS Scores 6 Weeks after Conservative Management of Carpometacarpal Thumb Arthritis.

Patient-reported outcome measures are being increasingly emphasized to assign value to care' given the current trend toward pay-for-performance healthcare. We sought to determine if the Patient-reported Outcomes Measurement Information System (PROMIS), a general questionnaire, is sensitive enough to detect improvement after corticosteroid injection or splinting/hand therapy for thumb carpometacarpal (CMC) arthritis. Methods: This is a retrospective study analyzing two groups with thumb CMC arthritis: 88 patients who received splinting/hand therapy and 6-week follow-up and 70 patients with steroid injection and 6-week follow-up. PROMIS Physical Function (PF), Pain Interference (PI), Depression, and Upper Extremity (UE) scores were collected at each visit. We used paired t-tests to compare 6-week follow-up scores to baseline scores within each group. Results: The mean age for the steroid injection group was 60.1 years old, and it was 61.8 years old for the returning splinting/hand therapy group. There were no significant differences in PROMIS PF, PI, Depression, or UE scores for patients who returned after 6 weeks of treatment with splinting/hand therapy. Moreover, at 6 weeks postinjection, PROMIS PF and UE scores marginally increased, whereas PI and Depression scores decreased with statistical significance. Conclusions: Hand surgeons should be aware of the limitations of PROMIS when evaluating patients after conservative treatment for thumb CMC arthritis. There were no significant differences in PROMIS scores for patients with thumb CMC arthritis who returned after receiving splinting/hand therapy for 6 weeks. Meanwhile, PI scores can be used primarily to monitor for improvement after steroid injection for thumb CMC arthritis.

Can Cervical and Lumbar Epidural Blood Patches Help Avoid Revision Surgery for Symptomatic Postoperative Dural Tears?

BACKGROUND: Incidental durotomies resulting in symptomatic postoperative cerebrospinal fluid (CSF) leaks can be treated with bedrest, subarachnoid lumbar drain, and surgical re-exploration. Another option is an epidural blood patch, which forms a clot over the dural tear in a minimally invasive manner. Our objective was to describe our center's outcomes and complications following epidural blood patches for symptomatic postoperative durotomies. METHODS: Patients undergoing spine surgeries at one institution from 2012-2020 were included. Patient charts were reviewed for demographic information, surgical data, rate of dural tear, type of repair, and use of blood patches postoperatively. RESULTS: A total of 1392 patients (726 male, 666 female, average age: 56.3 ± 15.4 years), including 436 cervical and 956 posterior thoracolumbar/lumbar spine surgeries were screened. There were 6 (1.4%) cervical, 64 (6.7%) lumbar, and a total of 70 (5.0%) patients with incidental dural tears/blebs. Of these patients, we identified 2 cervical and 8 lumbar spine patients with persistent CSF leaks who received epidural blood patches postoperatively. Nine of 10 (90%) had resolution of symptoms. One lumbar patient failed both an initial blood patch and subsequent surgical re-exploration, but had successful relief after a second blood patch. CONCLUSIONS: The incidence of dural tears/blebs was 1.4% in cervical, 6.7% in lumbar, and 5.0% in all spine surgeries. Of the 10 patients with symptomatic CSF leaks, 9 were successfully treated with blood patches. Targeted epidural blood patch is effective in treating symptomatic CSF leaks and minimizes the morbidity of surgical re-exploration.

The fourth column of the spine: Prevalence of sternal fractures and concurrent thoracic spinal fractures.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: This study aimed to identify the prevalence of concomitant thoracic spinal and sternal fractures and factors associated with concomitant fractures. SUMMARY OF BACKGROUND DATA: The sternum has been implicated in stability of the upper thoracic spine, and both bony structures are included in the stable upper thoracic cage. High force trauma to the thorax can cause multiple fractures to different upper thoracic cage components. METHODS: This is a retrospective analysis of electronic medical record data of patients treated at a Level 1 Trauma Center who underwent surgery for thoracic spinal fracture between 2008-2020. We recorded presence of concomitant sternal fracture, injury characteristics, hospital course data, and demographic information. RESULTS: 107 patients with thoracic spinal fractures had a sternal fracture prevalence of 18.7%. The average age was 53.2 [15-90]. 72 (67.3%) were male and 35 (32.7%) were female, 92 (85.9%) were White, 10 (9.3%) were African American, 3 (2.8%) were Hispanic, and 2 (1.9%) were Asian. The average age of patients with sternal fractures was 48.7 years, compared to those without sternal fractures, 54.3 years (P = 0.251). Patients with T1-T7 fractures [14 of 48 (29.2%)] had a significantly higher rate of sternal fractures compared to patients with T8-T12 fractures [6 of 59 (10.2%)] (P = 0.012). Patients with additional rib (P < 0.001), scapula (P = 0.01), clavicle fractures (P = 0.01), and those with multiple other thoracic fractures (P = 0.01) had significantly higher rates of sternal fractures compared to patients without these. Patients with concomitant sternal fractures [10 of 20 (50.0%)] had a significantly higher rate of respiratory complication during their hospital course than patients without concomitant sternal fracture [40 of 87 (46.0%)] (P < 0.001). Sex, age, mechanism of injury, fracture morphology, estimated blood loss during surgery, intraoperative complications, post-surgical intubation status, and post-surgical intubation duration were not associated with sternal fractures. CONCLUSIONS: The prevalence of concomitant thoracic spinal fracture and sternal fracture in our series is 18.7%. T1-T7 fractures and presence of rib, scapula, and clavicle fractures were significantly associated with the presence of sternal fractures. Presence of concomitant sternal fracture was significantly associated with respiratory complication during hospital course.

Double Crush Syndrome of the Upper Extremity.

¼: The double crush hypothesis originally proposed that compression of a peripheral nerve at a proximal site increases its susceptibility to additional distal lesions. ¼: The etiology of double crush syndrome is likely multifactorial as mechanical, systemic, pharmacologic, or environmental factors may increase a patient's susceptibility to this syndrome. ¼: To date, there remains no standardized definition of double crush syndrome, and there is no consensus on its exact pathophysiology or diagnostic criteria. ¼: Patients with double crush syndrome should be counseled that surgical repair may produce inferior outcomes compared with those who are treated for isolated entrapment neuropathies.

PROMIS Scores Should Not be Used in Isolation to Measure Outcomes in Lumbar Stenosis Patients.

STUDY DESIGN: Retrospective cross-sectional analysis. OBJECTIVE: The aim of this study was to establish the strength of relationship between the Patient-reported Outcomes Measurement Information System (PROMIS) Adult Depression (AD), Physical Function (PF), and Pain Interference (PI) with the Swiss Spinal Stenosis Questionnaire (SSSQ) in assessing lumbar spinal stenosis (LSS). SUMMARY OF BACKGROUND DATA: In 2009, there were >35,000 surgeries for LSS, which amounted to $1.65 billion in health care cost. By 2021, there will be >2.4 million people in the United States with symptomatic LSS. There is an increasing emphasis on patient-reported outcomes (PROs) to define value in medicine. Therefore, it would be beneficial to compare PROMIS, a universal PRO, against the SSSQ, the "criterion standard" for assessing LSS. METHODS: Eighty-two patients with LSS completing the PROMIS and SSSQ were enrolled. Per existing institutional protocol, PROMIS AD, PF, and PI were completed at every clinic visit. Linear regression analysis was then performed to evaluate how well the SSSQ and PROMIS scores correlated to each other. RESULTS: When linear regression was performed for pre-treatment values, the R2 value for the SSSQ PF versus PROMIS PF was 0.14 (P = 0.0008), whereas the R2 value for the SSSQ symptom severity versus PROMIS PI was 0.03 (P = 0.13). The R2 value for the combined SSSQ physical function and symptom severity versus PROMIS AD was 0.07 (P = 0.02). When post-treatment SSSQ satisfaction scores were correlated to postoperative PROMIS AD, PI, and PF scores, the R2 values for a good linear fit were 0.13, 0.25, and 0.18 respectively (P values: 0.01, 0.003, and 0.003). CONCLUSION: Pre-treatment PROMIS scores do not adequately capture the disease-specific impact of spinal stenosis, but postoperative PROMIS scores better reflect outcomes after surgery for LSS. PROMIS scores should not be used in isolation to assess outcomes in patients with LSS.Level of Evidence: 4.

PHYTOCHROME-INTERACTING FACTORs trigger environmentally responsive chromatin dynamics in plants.

The interplay between light receptors and PHYTOCHROME-INTERACTING FACTORs (PIFs) serves as a regulatory hub that perceives and integrates environmental cues into transcriptional networks of plants1,2. Although occupancy of the histone variant H2A.Z and acetylation of histone H3 have emerged as regulators of environmentally responsive gene networks, how these epigenomic features interface with PIF activity is poorly understood3-7. By taking advantage of rapid and reversible light-mediated manipulation of PIF7 subnuclear localization and phosphorylation, we simultaneously assayed the DNA-binding properties of PIF7, as well as its impact on chromatin dynamics genome wide. We found that PIFs act rapidly to reshape the H2A.Z and H3K9ac epigenetic landscape in response to a change in light quality. Furthermore, we discovered that PIFs achieve H2A.Z removal through direct interaction with EIN6 ENHANCER (EEN), the Arabidopsis thaliana homolog of the chromatin remodeling complex subunit INO80 Subunit 6 (Ies6). Thus, we describe a PIF-INO80 regulatory module that is an intermediate step for allowing plants to change their growth trajectory in response to environmental changes.

Readability of the Most Commonly Accessed Online Patient Education Materials Pertaining to Surgical Treatments of the Spine.

OBJECTIVE: The American Medical Association and National Institutes of Health have recommended that patient education materials should be written at the sixth-grade reading level to maximize patient comprehension. The objective of the present study was to evaluate the readability of Internet information for the 9 most common spinal surgeries. METHODS: We reviewed 90 online patient educational materials regarding the 9 most common spinal surgeries as reported by the North American Spine Society. A Google search was performed on March 23, 2019 for each surgery, and the top 10 most visited websites for each surgery were assessed for reading level using the Flesch-Kincaid formula. RESULTS: Using the Flesch-Kincaid formula, the average grade reading level of the 90 websites included was 12.82, with a reading ease of 37.04 ("difficult college"). Only 6 websites relayed information to patients at or below the national average of an eighth-grade reading level. The websites for bone morphogenic protein had the highest average grade reading level at 15.88 ± 2.6. Lumbar microscopic discectomy had the lowest average grade reading level at 10.37 ± 2.89. All surgical options discussed had an average readability above the recommended sixth-grade reading level. CONCLUSIONS: The most accessed online materials for common spinal surgeries, not only exceeded the readability limits recommended by both the American Medical Association and the National Institutes of Health, but they also exceeded the average reading ability of most adults in the United States. Patients, therefore, might not fully comprehend the information from commonly accessed websites regarding surgical spine treatment options.

Bone morphogenic protein-2 signaling in human disc degeneration and correlation to the Pfirrmann MRI grading system.

BACKGROUND CONTEXT: Back and neck pain secondary to disc degeneration is a major public health burden. There is a need for therapeutic treatments to restore intervertebral disc (IVD) composition and function. PURPOSE: To quantify ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens collected from patients undergoing surgery for disc degeneration, to correlate ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens to the 5-level Pfirrmann MRI grading system, and to compare ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression between cervical and lumbar degenerative disc specimens. STUDY DESIGN: An immunohistochemical study assessing ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in human control and degenerative IVD specimens. METHODS: Human IVD specimens were collected from surgical patients who underwent discectomy and interbody fusion at our institution between 1/2015 and 8/2017. Each patient underwent MRI prior to surgery. The degree of disc degeneration was measured according to the 5-level Pfirrmann MRI grading system. Patients were categorized into either the 1) control group (Pfirrmann grades I-II) or 2) degenerative group (Pfirrmann grades III-V). Histology slides of the collected IVD specimens were prepared and immunohistochemical staining was performed to assess ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in the control and degenerative specimens. Expression levels were also correlated to the Pfirrmann criteria. Lastly, the degenerative specimens were stratified according to their vertebral level and expression levels between the degenerative lumbar and cervical discs were compared. RESULTS: Fifty-two patients were enrolled; however, 2 control and 2 degenerative patients were excluded due to incomplete data sets. Of the remaining 48 patients, there were 12 control and 36 degenerative specimens. Degenerative specimens had increased expression levels of BMP-2 (p=.0006) and pSMAD1/5/8 (p<.0001). Pfirrmann grade 3 (p=.0365) and grade 4 (p=.0008) discs had significantly higher BMP-2 expression as compared to grade 2 discs. Pfirrmann grade 4 discs had higher pSMAD1/5/8 expression as compared to grade 2 discs (p<.0001). There were no differences in ALK3 or MMP-13 expression between the control and degenerative discs (p>.05). Stratifying the degenerative specimens according to their vertebral level showed no significant differences in expression levels between the lumbar and cervical discs (p>.05). CONCLUSIONS: BMP-2 and pSMAD1/5/8 signaling activity was significantly upregulated in the human degenerative specimens, while ALK3 and MMP-13 expression were not significantly changed. The expression levels of BMP-2 and pSMAD1/5/8 correlate positively with the degree of disc degeneration measured according to the Pfirrmann MRI grading system. CLINICAL SIGNIFICANCE: BMP-SMAD signaling represents a promising therapeutic target to restore IVD composition and function in the setting of disc degeneration.

Isolated MPTL reconstruction fails to restore lateral patellar stability when compared to MPFL reconstruction.

PURPOSE: To biomechanically evaluate MPTL reconstruction and compare it with two techniques for MPFL reconstruction in regard to changes in patellofemoral contact pressures and restoration of patellar stability. METHODS: This is an experimental laboratory study in eight human cadaveric knees. None had patellofemoral cartilage lesions or trochlear dysplasia as evaluated by conventional radiographs and MRI examinations. The specimens were secured in a testing apparatus, and the quadriceps was tensioned in line with the femoral shaft. Contact pressures were measured using the TekScan sensor at 30°, 60° and 90°. The sensor was placed in the patellofemoral joint through a proximal approach between femoral shaft and quadriceps tendon to not violate the medial and lateral patellofemoral complex. TekScan data were analysed to determine mean contact pressures on the medial and lateral patellar facets. Patellar lateral displacement was evaluated with the knee positioned at 30° of flexion and 9 N of quadriceps load, then a lateral force of 22 N was applied. The same protocol was used for each condition: native, medial patellofemoral complex lesion, medial patellofemoral ligament reconstruction (MPFL-R) using gracilis tendon, MPFL-R using quadriceps tendon transfer, and medial patellotibial ligament reconstruction (MPTL-R) using patellar tendon transfer. RESULTS: No statistical differences were found for mean and peak contact pressures, medial or lateral, among all three techniques. However, while both techniques of MPFL-R were able to restore the medial restraint, MPTL-R failed to restore resistance to lateral patellar translation to the native state (mean lateralization of the patella [mm]: native: 9.4; lesion: 22; gracilis MPFL-R: 8.1; quadriceps MPFL-R: 11.3; MPTL-R: 23.4 (p < 0.001). CONCLUSION: MPTL-R and both techniques for MPFL-R did not increase patellofemoral contact pressures; however, MPTL-R failed to provide a sufficient restraint against lateral patellar translation lateral translation in 30° of flexion. It, therefore, cannot be recommended as an isolated procedure for the treatment of patellar instability.

Treatment with Human Amniotic Suspension Allograft Improves Tendon Healing in a Rat Model of Collagenase-Induced Tendinopathy.

Treatment of tendon injuries is challenging, with neither conservative nor surgical approaches providing full recovery. Placental-derived tissues represent a promising tool for the treatment of tendon injuries. In this study, human amniotic suspension allograft (ASA) was investigated in a pre-clinical model of Achilles tendinopathy. Collagenase type I was injected in the right hind limb of Sprague Dawley rats to induce disease. Contralateral tendons were either left untreated or injected with saline as controls. Seven days following induction, tendons were injected with saline, ASA, or left untreated. Rats were sacrificed 14 and 28 days post-treatment. Histological and biomechanical analysis of tendons was completed. Fourteen days after ASA injection, improved fiber alignment and reduced cell density demonstrated improvement in degenerated tendons. Twenty-eight days post-treatment, tendons in all treatment groups showed fewer signs of degeneration, which is consistent with normal tendon healing. No statistically significant differences in histological or biomechanical analyses were observed between treatment groups at 28 days independent of the treatment they received. In this study, ASA treatment was safe, well-tolerated, and resulted in a widespread improvement of the tissue. The results of this study provide preliminary insights regarding the potential use of ASA for the treatment of Achilles tendinopathy.

Bone-Plug Versus Soft Tissue Fixation of Medial Meniscal Allograft Transplants: A Biomechanical Study.

BACKGROUND: It is controversial whether soft tissue fixation only and bone-plug techniques for medial meniscal allograft transplantation provide equivalent fixation and restoration of load distribution. Prior studies on this topic did not re-create the clinical situation with use of size-, side-, and compartment-matched meniscal transplants. HYPOTHESIS: Both techniques will provide equivalent fixation of the meniscal transplant and restore load distribution and contact pressures similar to those of the native knee. STUDY DESIGN: Controlled laboratory study. METHODS: Nine fresh-frozen human cadaveric knees underwent mean contact pressure, mean contact area, and peak contact pressure evaluation in 4 medial meniscal testing conditions (native, total meniscectomy, bone-plug fixation, and soft tissue fixation) at 3 flexion angles (0°, 30°, and 60°) using Tekscan sensors under a 700-N axial load. RESULTS: Medial meniscectomy resulted in significantly decreased contact area and increased contact pressure compared with the native condition at all flexion angles (P < .0001). Compared with the native state, soft tissue fixation demonstrated significantly higher mean contact pressure and lower mean contact area at 0° and 30° of flexion (P < .05), while bone-plug fixation showed no significant difference. There was no significant difference in peak contact pressure between study conditions. CONCLUSION: Total medial meniscectomy leads to significantly worsened load distribution within the knee. Medial meniscal allograft transplantation can restore load parameters close to those of the native condition. The bone-plug technique demonstrated improved tibiofemoral contact pressures compared with soft tissue fixation. CLINICAL RELEVANCE: Medial meniscal allograft transplantation with bone-plug fixation is a viable option to restore biomechanics in patients with meniscal deficiency.

No effect of topical application of tranexamic acid on articular cartilage.

PURPOSE: The objective of this study was to evaluate potential cytotoxicity of TXA on articular cartilage by assessing chondrocyte viability of osteochondral explants after exposure to different concentrations and durations of TXA. METHODS: Thirty-nine osteochondral plugs (OCPs) were harvested from three adult Yucatan minipigs immediately after their death. OCPs were divided into 13 groups exposed to different concentrations of TXA (1, 2 and 4 mg/ml in saline solution) for 1, 3 and 6 h. Negative controls were exposed to saline solution for 0, 1, 3 and 6 h. Chondrocyte viability was assessed by Live/Dead cell assay and calculated as the ratio of live cells (green fluorescence) to overall cells (green + red cells) for each concentration of TXA and time point in a 50-µm scanned image. RESULTS: No correlation was found between chondrocyte viability, and TXA concentration and time of exposure. Overall, chondrocyte viability ranged from 90 to 99%. There was no statistical difference among control group, 1, 2 and 4 mg/ml TXA solutions at each time point [1 h (n.s.), 3 h (n.s.), 6 h (n.s.)]. Similarly, no statistical difference among groups was observed when comparing cell viability at 1, 3 and 6 h of TXA exposure, (Fig. 2) [1 mg/ml (n.s.), 2 mg/ml (n.s.), and 4 mg/ml (n.s.)]. CONCLUSIONS: In conclusion, doses of TXA approximating the current clinical protocols for topical use did not demonstrate any cytotoxic effects on cartilage explants in a Yucatan mini pig model. Thus, supporting the topical application for procedures with intact cartilage, such as partial knee replacement surgery and cartilage repair procedures.

A New Technique for Distalization of the Tibial Tubercle That Allows Preservation of the Proximal Buttress.

BACKGROUND: Tibial tubercle osteotomy (TTO) is a treatment option for patients with patellofemoral instability and chondrosis. Occasionally, these patients also present with patella alta, and distalization of the tibial tubercle is desirable. Free distal transfer of the tubercle, however, can compromise mechanical stability of the osteotomy construct, leading to loss of fixation. PURPOSE: To evaluate alternative TTO proximal cut geometries to investigate whether these can result in tubercle distalization while preserving the proximal buttress. STUDY DESIGN: Descriptive laboratory study. METHODS: Three variants of TTO cut geometry were evaluated on Sawbones as well as cadaveric knees. The proximal cut of the osteotomy was modified in 2 axes: anterior-posterior (AP) and medial-lateral (ML). Three variations were used: ML neutral/AP neutral, ML 30° proximal/AP neutral, and ML neutral/AP 30° proximal. The medial cut plane was 45° for all specimens. Tibial tubercle position was evaluated before and after osteotomy to calculate anteriorization, medialization, and distalization. RESULTS: Distalization was achieved with all variants. Increasing the inclination angle of the proximal cut in the AP and ML axes resulted in maximum distalization. A proximally directed cut yielded significantly more distalization when performed in the AP axis than in the ML axis (P < .05). Even the standard, neutral cut resulted in 5 mm of distalization. CONCLUSION: Fulkerson osteotomy allows 3-dimensional repositioning of the tibial tubercle and has historically been utilized to achieve anteriorization and medialization. Even the neutral cut of a standard TTO resulted in distalization, which is relevant for patients with preexisting patella baja. Modification of the proximal cut increased distalization of the tubercle while preserving the proximal buttress, a potential benefit for construct stability. CLINICAL RELEVANCE: These results provide a guideline for adjusting the proximal cut geometry in Fulkerson TTO to meet specific patient needs.

Cell-Seeded Autologous Chondrocyte Implantation: A Simplified Implantation Technique That Maintains High Clinical Outcomes.

BACKGROUND: The use of autologous chondrocyte implantation (ACI) remains limited, even though multiple studies have demonstrated success rates exceeding 75%. The procedure is perceived as invasive and technically challenging, presenting barriers to more widespread adoption. Purpose/Hypothesis: The objective of this study was to investigate whether outcomes and the failure rate of a simplified ACI technique (cs-ACI) were comparable with those of the more complicated traditional technique of a chondrocyte suspension injected under a collagen membrane (cACI). We hypothesized that the change in technique would not negatively affect outcomes. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Thirty-nine patients treated with the cs-ACI technique fulfilled the inclusion requirements. A group of 45 patients treated previously with standard cACI was used as a comparison. The functional outcomes were prospectively collected both preoperatively and postoperatively at the last follow-up. Failure was defined as any graft removal of more than 25% of the original defect size. Magnetic resonance imaging was performed postoperatively, and scans were assessed using a modified MOCART (magnetic resonance observation of cartilage repair tissue) scoring system. RESULTS: Group demographics were not significantly different, except for the defect size and mean follow-up: 4.09 years in the cACI group and 2.46 years in the cs-ACI group. Significant improvements were seen in all outcome measures except the Tegner score from the preoperative baseline to the latest follow-up for both the cACI group (International Knee Documentation Committee [IKDC] score, from 42.0 to 63.4; Knee injury and Osteoarthritis Outcome Score [KOOS]-Pain subscore, from 58.7 to 77.1; Lysholm score, from 57.2 to 69.7; and Tegner score, from 3.5 to 4.2) and the cs-ACI group (IKDC score, from 45.6 to 68.0; KOOS-Pain subscore, from 66.6 to 84.7; Lysholm score, from 53.7 to 75.4; and Tegner score, from 3.2 to 3.8). No significant difference was found between the groups at the latest follow-up. The failure rate at 2 years was not significantly different, while the total failure rate over the entire study period was significantly lower in the cs-ACI group than the cACI group (5% vs 24%, respectively). The overall MOCART score was not significantly different between the groups. CONCLUSION: The treatment of full-thickness articular cartilage defects with a simplified cell-seeded ACI technique demonstrated no significant differences in the failure rate and patient-reported outcomes when compared with a standard technique utilizing interrupted sutures and the injection of a cell suspension under a collagen membrane.

An Exploratory Human Laboratory Experiment Evaluating Vaporized Cannabis in the Treatment of Neuropathic Pain From Spinal Cord Injury and Disease.

UNLABELLED: Using 8-hour human laboratory experiments, we evaluated the analgesic efficacy of vaporized cannabis in patients with neuropathic pain related to injury or disease of the spinal cord, most of whom were experiencing pain despite traditional treatment. After obtaining baseline data, 42 participants underwent a standardized procedure for inhaling 4 puffs of vaporized cannabis containing either placebo, 2.9%, or 6.7% delta 9-THC on 3 separate occasions. A second dosing occurred 3 hours later; participants chose to inhale 4 to 8 puffs. This flexible dosing was used to attempt to reduce the placebo effect. Using an 11-point numerical pain intensity rating scale as the primary outcome, a mixed effects linear regression model showed a significant analgesic response for vaporized cannabis. When subjective and psychoactive side effects (eg, good drug effect, feeling high, etc) were added as covariates to the model, the reduction in pain intensity remained significant above and beyond any effect of these measures (all P < .0004). Psychoactive and subjective effects were dose-dependent. Measurement of neuropsychological performance proved challenging because of various disabilities in the population studied. Because the 2 active doses did not significantly differ from each other in terms of analgesic potency, the lower dose appears to offer the best risk-benefit ratio in patients with neuropathic pain associated with injury or disease of the spinal cord. PERSPECTIVE: A crossover, randomized, placebo-controlled human laboratory experiment involving administration of vaporized cannabis was performed in patients with neuropathic pain related to spinal cord injury and disease. This study supports consideration of future research that would include longer duration studies over weeks to months to evaluate the efficacy of medicinal cannabis in patients with central neuropathic pain.