Augmenting Osteochondral Autograft Transplantation and Bone Marrow Aspirate Concentrate with Particulate Cartilage Extracellular Matrix Is Associated With Improved Outcomes
Background: Osteochondral autograft transplant (OAT) is often used to treat large osteochondral lesions of the talus and is generally associated with good outcomes. The addition of adjuncts such as cartilage extracellular matrix with bone marrow aspirate concentrate (ECM-BMAC) may further improve the OAT procedure but have not been thoroughly studied. We hypothesized that the placement of ECM-BMAC around the OAT graft would improve radiographic and patient-reported outcomes following OAT. Methods: Patients who received OAT, with ECM-BMAC or BMAC alone, were screened and their charts were reviewed. For patients who did receive ECM-BMAC, the mixture was spread around the edges of the OAT plug and into any surrounding areas of cartilage damage. Survey and radiographic data were collected. Average follow-up in both groups was over 2 years. Magnetic resonance imaging scans were scored using the Magnetic Resonance Observation of Cartilage Tissue (MOCART) system. Outcomes were compared statistically between groups. Results: Patients treated with ECM-BMAC (n = 34) demonstrated significantly greater improvement of scores in the FAOS categories Symptoms (17 vs −3; P = .02) and Sports Activities (40 vs 7; P = .02), and the MOCART category Subchondral Lamina ( P = .008) compared to those treated with BMAC alone (n = 30). They also experienced significantly lower rates of postoperative cysts (53% vs 18%, P = .04) and edema (94% vs 59%, P = .02). Conclusion: The addition of ECM-BMAC to OAT was associated with improved imaging and clinical outcomes compared to OAT with BMAC alone.
Abstract Postoperative ankle imaging requires knowledge of the underlying surgical techniques, the usefulness of various imaging modalities, as well as an appreciation for the desired clinical outcomes. Surgical procedures discussed in this article are tibiotalar fracture fixation, tibiotalar, subtalar, and tibiotalocalcaneal arthrodesis, total ankle arthroplasty, talar osteochondral lesion repair and grafting, lateral ligamentous repair and reconstruction, and peroneal and Achilles tendon repair and reconstruction. Imaging can play a vital role in determining if the expected outcome has been achieved and identifying complications, with particular emphasis placed on the use of radiographs, computed tomography (including weight-bearing), magnetic resonance imaging, and ultrasonography.
The Effect of Patellar Surface Morphology on Subchondral Bone Alignment When Matching Patellar Osteochondral Allografts to the Central Ridge of the Patella
Background: Cartilage transplants in the patellofemoral joint have demonstrated lower success rates than in the femoral condyles. This is likely related to the more complex morphology and biomechanics of the joint. While previous studies have evaluated cartilage surface matching and congruence, little work has been done to study the associated subchondral bone congruency in these grafts. Purpose: To determine if differences in patellar morphology play a role in the alignment of the donor patellar osteochondral allograft subchondral bone with the native patellar subchondral bone. Study Design: Controlled laboratory study. Methods: A total of 20 (10 Wiberg I and 10 Wiberg II/III) fresh-frozen human patellae were designated as recipients and size-matched to both a Wiberg I and a Wiberg II/III patellar donor. A 16-mm osteochondral allograft transplant to the central ridge of the patella was performed in random order with each matched donor. Transplanted patellae underwent a nano—computed tomography (nano-CT) scan, were digitally reconstructed, and were superimposed on the initial nano-CT scan of the native recipient patella. MATLAB was used to determine the surface height deviation between the native and donor subchondral bone surfaces. DragonFly 3-dimensional imaging software was used to measure subchondral bone step-off heights at the native-donor interface. Differences between matched and unmatched grafts were compared using a 2-way analysis of variance and the Sidak post hoc test. Results: Subchondral bone surface deviation did not differ between Wiberg matched and unmatched allografts. The step-off height was significantly greater in unmatched (1.38 ± 0.49 mm) compared with matched (1.14 ± 0.52 mm) plugs ( P = .015). The lateral quadrant step-off differed between matched (0.89 ± 0.43 mm) and unmatched (1.60 ± 0.78 mm) grafts ( P = .007). Conclusion: While unmatched Wiberg patellar osteochondral allograft implantation did not result in significantly different subchondral bone surface height deviations, there was a significant difference in the circumferential subchondral bone step-off height in the lateral quadrant. Further investigation using finite element analysis modeling will help determine the role of subchondral bone surface on shear and compression force distributions in these areas. Clinical Relevance: Given that subchondral bone stiffness and morphology play a role in cartilage health, subchondral bone congruency may play a role in graft survival. Understanding how this congruency plays a role in cartilage force distribution will help surgeons improve the long-term success of osteochondral allograft transplants.
Prevalence of Cannabinoid (CBD) Use in Orthopaedic Sports Medicine Patients
Background: Although there is some evidence that cannabinoid (CBD) products may provide a therapeutic effect for musculoskeletal pain, little is known about the usage patterns or their prevalence of use in orthopaedic sports medicine patients. Purpose: To report the prevalence and perceived self-efficacy of CBD products in patients evaluated in an orthopaedic sports medicine clinic. Study Design: Descriptive epidemiology study. Level of evidence, 2. Methods: The study population consisted of new patients who visited an orthopaedic surgery sports medicine clinic at a large academic center for consultation with a surgeon between August 2020 and March 2021. All patients were asked to complete a survey that assessed perceived pain and effectiveness of CBD products and other nonsurgical treatment modalities using the Single Assessment Numeric Evaluation score (range, 0-100) and the Numeric Pain Rating Scale (NRS). Descriptive factors were collected via chart review. Descriptive statistics were used to characterize the data. Results: Overall, 823 patients completed the survey (45.4% female; mean age, 51 years [range, 18-87 years]; mean body mass index, 28.9 [range, 17.2-58.4]). Body areas involved included 285 shoulders, 44 elbows, 76 hips, 276 knees, 58 ankles, and 77 other. Of these patients, 19% (152/823) endorsed the use of CBD products before their initial evaluation. The mean NRS for pain was significantly different between non-CBD users and CBD users (5.6 vs 6.1; P = .029). CBD users were significantly more likely to have tried other nonoperative modalities compared with nonusers, including nonsteroidal anti-inflammatory drugs (79.6% vs 69.8%; P = .032), bracing (44.7% vs 34.6%; P = .024), steroid injections (38.8% vs 21.6%; P < .001), and physical therapy (54% vs 36.1%; P < .001). In addition, 30.9% of CBD utilizers reported marijuana use compared with 2.8% of non-CBD users ( P < .001) for management of their pain. Conclusion: In the current study, 19% of patients had used CBD products to manage joint-related issues. Sports medicine providers should be aware of this high incidence of usage and the potential interactions CBD products may have with other treatment modalities. Further studies are needed to assess the effectiveness of CBD as a therapeutic agent and the specific interactions it has with other drugs and other forms of treatment.
Publicly Available Pricing Information for Orthopaedic Upper Extremity Procedures in the United States Lacks Transparency and Consistency Between Major Hospitals
Purpose The purpose of this study was to assess the price variation of various Medicare severity diagnosis‐related group codes for orthopaedic upper extremity procedures for the top 20 orthopaedic hospitals using chargemaster price listings from each hospital. Methods The top 20 orthopaedic hospitals in the United States were determined by querying the U.S. News and World Report ’s 2020 orthopaedic hospital ranking. This report ranks orthopaedic hospitals according to 4 major domains: outcomes, structure, process/expert opinion, and patient experience. Chargemaster data for the top 20 orthopaedic hospitals was compiled from their websites. Five DRG codes that represented orthopaedic upper extremity procedures were selected, and the pricing information for each was extracted from hospital chargemasters. The median income and cost‐of‐living index were also compiled for the county that each hospital is located in so that pricing data could be compared to economic measures through regression analysis. Results Of the top 20 orthopaedic hospitals, 18 had publicly available pricing information in DRG format on their websites. The DRG code with the highest pricing variability was Hand Injury Procedures (DRG 906; range, $12,832‐$253,633). The procedure with the least pricing variability was Hand or Wrist Procedures (DRG 514; range, $24,533‐$128,403). Additionally, only the cost of living index was a statistically significant predictor of procedure pricing with a weak correlation. Conclusion Hospital chargemaster listings are lacking in 2 major areas: true price transparency and standardization/consistency between hospitals. Chargemaster data are often difficult to find, confusing to patients, and inaccurate. Additionally, the price range for a single DRG code can also vary substantially depending on the hospital. It is possible that hospitals located in areas with high costs of living and median incomes would charge higher prices, but these factors were not found to support this hypothesis.
Compartment Syndrome following Below-Knee Amputation
In the setting of below-knee amputation, compartment syndrome is a rare complication. Early clinical symptoms of an acute compartment syndrome following below-knee amputation can mimic or be masked by postoperative pain management. We present the case of a 38-year-old male with a significant past medical history of Proteus syndrome who underwent an elective transtibial below-knee amputation. Following surgery, the patient had extensive postoperative pain and high pain medication requirements and returned to the operating room for irrigation and debridement due to suspicion of an infection. Upon return to the operating room to manage the infection, the necrotic tissue was discovered and removed which had developed due to a suspected missed acute compartment syndrome. The necrotic tissue secondary to the compartment syndrome subsequently resulted in infection. Multiple irrigation and debridement procedures were performed to further manage the infection, and ultimately, the patient was deemed stable for discharge. Acute compartment syndrome (ACS) following below-knee amputation (BKA) is a rarely documented but critical complication. This case describes the unique setting in which a compartment syndrome can be masked due to postoperative pain management and infection. Orthopedic surgeons should be aware of the varying risk factors and presentations of an acute compartment syndrome (ACS) as it can occur and is a devastating complication.
Talus Visualization in Ankle Fractures: How Much Are We Really Seeing?
Background: Despite appropriate care, a subset of patients with ankle fractures has persistent pain. This condition may be associated with intra-articular pathology, which is present up to 65% of the time. Purpose: To quantify how much of the talus is visible through an open approach to a standard supination external rotation bimalleolar ankle fracture as a percentage of the entire weightbearing surface of the talus. Study Design: Descriptive laboratory study. Methods: Standard ankle approaches to lateral and medial malleolar fractures were performed in 4 cadaveric ankles from 2 cadavers. Osteotomies were made to simulate a supination external rotation bimalleolar ankle fracture based on the Lauge-Hansen classification. The visible segments of talar cartilage were removed. The tali were then exhumed, and the entire weightbearing superior portion of the talus was assessed and compared with the amount of cartilage removed by an open approach. The mean of the data points as well as the 95% confidence interval were calculated. Results: Four ankle specimens from 2 cadavers were used for these measurements. The mean surface area of the talus was 14.0 cm 2 (95% CI, 13.3-14.7 cm 2 ), while the mean area visible via an open approach was 2.1 cm 2 (95% CI, 0.5-3.6 cm 2 ). The mean proportion of the talus visualized via an open approach was 14.8% (95% CI, 3.6-26.1%). Conclusion: These findings indicate that the true area of weightbearing talar surface visible during an open exposure may be less than what many surgeons postulate. Clinical Relevance: Only a small fracture of the talus is visible via an open approach to the talus during fracture fixation. This could warrant arthroscopic evaluation of these injuries to evaluate and treat osteocondral lesions resulting from ankle fractures.
Between 2000 and 2020, Reimbursement for Orthopaedic Foot and Ankle Surgery Decreased by 30%
Purpose To examine and analyze Medicare reimbursement rates from 2000 to 2020 for orthopaedic foot and ankle procedures. Methods The 20 most used orthopaedic foot and ankle surgical procedures were gathered from the Centers for Medicare & Medicaid Services website using the Medicare Provider Utilization and Payment Data Public Use File 2017. The reimbursement data for each code were gathered from The Physician Fee Schedule Look‐Up Tool from Centers for Medicare & Medicaid Services. The reimbursement values were adjusted for inflation to 2020 U.S. dollars using the consumer price index. Results The average inflation‐adjusted reimbursement for included procedures decreased by 30% from 2000 to 2020. The greatest mean decreases were observed for “correction of hallux valgus” (–47%) and “partial excision of foot bone” (–41%). The procedures with the smallest mean decreases were observed in “treatment of “Amputation of toe” (–19%) and “closed treatment of metatarsal fracture” (–7%). Conclusions From 2000 to 2020, Inflation‐adjusted Medicare reimbursement for foot and ankle surgery decreased by 30%. Level of Evidence IV; economic analysis.
Preoperative Intra-articular Steroid Injections as Predictors of Hip Arthroscopy: 2-Year Outcomes
Background: In patients with femoroacetabular impingement, preoperative diagnostic injections are commonly used to establish a diagnosis of intra-articular pathology. In some cases, intra-articular steroid injections are also used for therapeutic purposes. Purpose/Hypothesis: The purpose of this study was to determine if a positive response to intra-articular steroid injection was predictive of superior outcomes after hip arthroscopy to determine if the response to intra-articular steroid injection was predictive of outcomes after hip arthroscopy. It was hypothesized that a positive response to a preoperative hip injection would be predictive of improved short- to midterm outcomes after hip arthroscopy. Study Design: Cohort study; Level of evidence, 3. Methods: This was a retrospective study of 208 patients who elected to have ultrasound-guided intra-articular steroid injection before they underwent hip arthroscopy between January 2016 and December 2016. Patients were divided into 2 groups: those who showed improvement in pain after the injection (steroid responder group) and those who showed no response (nonresponder group). The authors compared the preoperative and 2-year postoperative patient-reported outcomes (modified Harris Hip Score [mHHS] and Hip Outcome Score–Activities of Daily Living [HOS-ADL]) and radiographic findings between groups. Clinical endpoints, including rates of revision and conversion to total hip arthroplasty, were also reviewed. Results: There were 88 patients in the nonresponder group and 120 patients in the responder group, with no significant between-group differences in preoperative descriptive variables. The responder group had significantly higher 2-year mHHS and HOS-ADL, pre- to postoperative change in mHHS and HOS-ADL, percentage of patients achieving the patient acceptable symptomatic state (PASS) on the mHHS, and percentage of patients reaching the minimum clinically important difference and the PASS on the HOS-ADL. There was no difference in Tönnis grade, acetabular labrum articular disruption grade, revision rate, or conversion to total hip arthroplasty between the 2 groups. Conclusion: The response to preoperative intra-articular injection did aid in predicting 2-year patient-reported outcomes of hip arthroscopy for femoroacetabular impingement. Overall, the result of a preoperative intra-articular injection can be a helpful clinical tool for surgical decision-making and counseling patients on expected outcomes after hip arthroscopy.
The Effect of Patellar Surface Morphology On Subchondral Bone Alignment When Matching Patellar Osteochondral Allografts (206)
Objectives: Recent research has shown that implanting a patellar osteochondral allograft with a non-matched surface morphology (i.e., Wiberg classification) does not create increased chondral surface deviation or circumferential step-off in the donor plug compared to the native patella. While much of the research on patellar osteochondral allografts has been focused on chondral surface matching, little has been done to determine if the subchondral bone alignment at the donor:native interface plays a role in graft healing, local force distribution, and long term success of the allograft transplant. Previous work in our lab demonstrated that even when the patellar cartilage surface was well matched, notable differences in subchondral bone alignment were observed. The purpose of this study was therefore to use surface contour mapping of subchondral bone to determine if differences in Wiberg classification play a role in the ability of donor patellar osteochondral allograft subchondral bone to align with the native patellar subchondral bone when treating osteochondral defects of the patellar apex. The hypothesis was that patellar surface morphology would have an effect on subchondral bone surface height deviation and circumferential step-off when performing osteochondral allograft transplants of the patellar apex. Methods: Sixty fresh frozen human patellae were acquired from a national donor procurement company. Twenty (10 Wiberg I and 10 Wiberg II/III) patellae were designated as the recipient and then nano-CT scanned. Each recipient was size-matched (within ±2mm tibial width) to both a Wiberg I and a Wiberg II/III patellar donor. A 16mm circular osteochondral “defect” centered on the central ridge of the patella was then created in the recipient patella. A randomly-ordered donor Wiberg I or Wiberg II/III plug was harvested from a homologous location and transplanted into the recipient. The recipient was then nano-CT scanner, digitally reconstructed, and superimposed on the initial nano-CT scan of the native recipient patella. After careful atraumatic removal of the first donor plug, the process was repeated using the other allograft plug. MATLAB was used to determine the root mean square (RMS) surface height deviation between the native and donor subchondral bone surfaces. Dragonfly 3D imaging software was used to measure the RMS subchondral bone step-off height at 3° increments around the circumference of the graft. Surface height deviation and circumferential step-off height were analyzed for the whole surface and by quadrant to determine if there were local differences. ANOVA was used to compare surface deviation and step-off heights between matched and unmatched grafts. Sidak’s multiple comparison test was used to complete sub-analysis between patellar graft quadrants. Comparisons were made between matched and unmatched grafts in terms of the RMS surface height deviation and step-off, as well as in the percentage of measurements that were more than 0.5mm, 1mm, and 2mm proud or sunken relative to the native surface. Results: There were no significant differences in RMS subchondral bone surface height deviation between matched and unmatched Wiberg plugs as a whole or by quadrant (RMS range = 0.69 to 0.97mm, p = 0.45 – 1.0). There was a significant difference in RMS circumferential step-off height between matched (1.14 ± 0.52mm) and unmatched (1.38 ± 0.49mm) Wiberg plugs ( p=0.015). The majority of these increased step-off measurements occurred in the lateral quadrant with lateral quadrant RMS step-off of 0.89 ± 0.43mm in matched grafts and 1.60 ± 0.78mm in unmatched grafts ( p=0.007). There was also a significant difference in the percent of step-off measurements greater than 2mm sunken in the lateral quadrant between matched and unmatched grafts (5.17 ± 20.87% matched, 24.5 ± 36.39% unmatched, p=0.028). There were no significant differences between matched and unmatched grafts for any other comparison using 0.5, 1, or 2mm cut-offs for circumferential step-off or surface height deviation. Combining all allografts, the respective proportion of surface deviation and circumferential step-off height measurements that were above the stated thresholds were as follows: 31% and 34% for a 0.5mm threshold, 15% and 21% for a 1mm threshold, and 2% and 8% for a 2mm threshold. Conclusions: While unmatched Wiberg patella osteochondral allograft implantation did not result in significantly different subchondral bone surface height deviations, there were significant differences in circumferential subchondral bone step-off heights. The majority of step-off height differences between Wiberg matched and unmatched osteochondral allografts occurred in the lateral quadrant. In comparison to previous data evaluating differences in the cartilage surface match in these patellar OCA transplants, the deviations and step-off heights in the subchondral bone identified in the current study were approximately 0.5mm greater than the differences in the cartilage surface. These findings therefore suggest there is greater variability in the alignment of the subchondral bone in these patellar osteochondral allografts than there is in the cartilage surface. Further investigation using finite element analysis modeling will help determine the implications of subchondral bone surface deviation and circumferential step-off on local cartilage:bone compression and shear force distribution. These studies may shed light on the mechanisms of failure in patellar osteochondral transplants and may help to better understand the contribution of subchondral bone alignment in OCA healing and long-term outcome.