Subchondral Bone Alignment in Osteochondral Allograft Transplants for Large Oval Defects of the Medial Femoral Condyle: Comparison of Lateral versus Medial Femoral Condyle Donors.

OBJECTIVE: Supply-demand mismatch of medial femoral condyle (MFC) osteochondral allografts (OCAs) remains a rate-limiting factor in the treatment of osteochondral defects of the femoral condyle. Surface contour mapping was used to determine whether a contralateral lateral femoral condyle (LFC) versus ipsilateral MFC OCA differs in the alignment of donor:native subchondral bone for large osteochondral defects of the MFC. DESIGN: Thirty fresh-frozen human femoral condyles were matched by tibial width into 10 groups of 3 condyles (MFC recipient, MFC donor, and LFC donor) each for 3 cartilage surgeons (90 condyles). The recipient MFC was imaged using nano-computed tomography scan. Donor oval grafts were harvested from each matched condyle and transplanted into a 17 mm × 36 mm defect created in the recipient condyle. Following the first transplant, the recipient condyle was imaged and superimposed on the native condyle nano-CT scan. The donor plug was removed and the process repeated for the other donor. Surface height deviation and circumferential step-off height deviation were compared between native and donor subchondral bone surfaces for each transplant. RESULTS: There was no statistically significant difference in mean subchondral bone surface deviation (LFC = 0.87 mm, MFC = 0.76 mm, P = 0.07) nor circumferential step-off height (LFC = 0.93 mm, MFC = 0.85 mm, P = 0.09) between the LFC and MFC plugs. There were no significant differences in outcomes between surgeons. CONCLUSIONS: There were no significant differences in subchondral bone circumferential step-off or surface deviation between ipsilateral MFC and contralateral LFC oval-shaped OCAs for 17 mm × 36 mm defects of the MFC.

A modified Delphi consensus statement on patellar instability: part I.

Aims: The aim of this study was to establish consensus statements on the diagnosis, nonoperative management, and indications, if any, for medial patellofemoral complex (MPFC) repair in patients with patellar instability, using the modified Delphi approach. Methods: A total of 60 surgeons from 11 countries were invited to develop consensus statements based on their expertise in this area. They were assigned to one of seven working groups defined by subtopics of interest within patellar instability. Consensus was defined as achieving between 80% and 89% agreement, strong consensus was defined as between 90% and 99% agreement, and 100% agreement was considered to be unanimous. Results: Of 27 questions and statements on patellar instability, three achieved unanimous consensus, 14 achieved strong consensus, five achieved consensus, and five did not achieve consensus. Conclusion: The statements that reached unanimous consensus were that an assessment of physeal status is critical for paediatric patients with patellar instability. There was also unanimous consensus on early mobilization and resistance training following nonoperative management once there is no apprehension. The statements that did not achieve consensus were on the importance of immobilization of the knee, the use of orthobiologics in nonoperative management, the indications for MPFC repair, and whether a vastus medialis oblique advancement should be performed.

A modified Delphi consensus statement on patellar instability: part II.

Aims: The aim of this study was to establish consensus statements on medial patellofemoral ligament (MPFL) reconstruction, anteromedialization tibial tubercle osteotomy, trochleoplasty, and rehabilitation and return to sporting activity in patients with patellar instability, using the modified Delphi process. Methods: This was the second part of a study dealing with these aspects of management in these patients. As in part I, a total of 60 surgeons from 11 countries contributed to the development of consensus statements based on their expertise in this area. They were assigned to one of seven working groups defined by subtopics of interest. Consensus was defined as achieving between 80% and 89% agreement, strong consensus was defined as between 90% and 99% agreement, and 100% agreement was considered unanimous. Results: Of 41 questions and statements on patellar instability, none achieved unanimous consensus, 19 achieved strong consensus, 15 achieved consensus, and seven did not achieve consensus. Conclusion: Most statements reached some degree of consensus, without any achieving unanimous consensus. There was no consensus on the use of anchors in MPFL reconstruction, and the order of fixation of the graft (patella first versus femur first). There was also no consensus on the indications for trochleoplasty or its effect on the viability of the cartilage after elevation of the osteochondral flap. There was also no consensus on postoperative immobilization or weightbearing, or whether paediatric patients should avoid an early return to sport.

Factors Associated With Humeral Avulsion of Glenohumeral Ligament Lesions in Patients With Anterior Shoulder Instability: An Analysis of the MOON Shoulder Instability Cohort.

Background: Humeral avulsion of the glenohumeral ligament (HAGL) lesions are an uncommon cause of anterior glenohumeral instability and may occur in isolation or combination with other pathologies. As HAGL lesions are difficult to detect via magnetic resonance imaging (MRI) and arthroscopy, they can remain unrecognized and result in continued glenohumeral instability. Purpose: To compare patients with anterior shoulder instability from a large multicenter cohort with and without a diagnosis of a HAGL lesion and identify preoperative physical examination findings, patient-reported outcomes, imaging findings, and surgical management trends associated with HAGL lesions. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Patients with anterior glenohumeral instability who underwent surgical management between 2012 and 2020 at 11 orthopaedic centers were enrolled. Patients with HAGL lesions identified intraoperatively were compared with patients without HAGL lesions. Preoperative characteristics, physical examinations, imaging findings, intraoperative findings, and surgical procedures were collected. The Student t test, Kruskal-Wallis H test, Fisher exact test, and chi-square test were used to compare groups. Results: A total of 21 HAGL lesions were identified in 915 (2.3%) patients; approximately one-third (28.6%) of all lesions were visualized intraoperatively but not identified on preoperative MRI. Baseline characteristics did not differ between study cohorts. Compared with non-HAGL patients, HAGL patients were less likely to have a Hill-Sachs lesion (54.7% vs 28.6%; P = .03) or an anterior labral tear (87.2% vs 66.7%; P = .01) on preoperative MRI and demonstrated increased external rotation when their affected arm was positioned at 90° of abduction (85° vs 90°; P = .03). Additionally, HAGL lesions were independently associated with an increased risk of undergoing an open stabilization surgery (odds ratio, 74.6 [95% CI, 25.2-221.1]; P < .001). Conclusion: Approximately one-third of HAGL lesions were missed on preoperative MRI. HAGL patients were less likely to exhibit preoperative imaging findings associated with anterior shoulder instability, such as Hill-Sachs lesions or anterior labral pathology. These patients underwent open procedures more frequently than patients without HAGL lesions.

Cartilage thickness mismatches in patellar osteochondral allograft transplants affect local cartilage stresses.

Osteochondral allograft implantation is a form of cartilage transplant in which a cylindrical graft of cartilage and subchondral bone from a donor is implanted into a patient's prepared articular defect site. No standard exists for matching the cartilage thickness of the donor and recipient. The goal of this study was to use finite element (FE) analysis to identify the effect of cartilage thickness mismatches between donor and recipient cartilage on cartilage stresses in patellar transplants. Two types of FE models were used: patient-specific 3D models and simplified 2D models. 3D models highlighted which geometric features produced high-stress regions in the patellar cartilage and provided ranges for the parameter sweeps that were conducted with 2D models. 2D models revealed that larger thickness mismatches, thicker recipient cartilage, and a donor-to-recipient cartilage thickness ratio (DRCR) < 1 led to higher stresses at the interface between the donor and recipient cartilage. A surface angle between the donor-recipient cartilage interface and cartilage surface normal near the graft boundary increased stresses when DRCR > 1, with the largest increase observed for an angle of 15°. A surface angle decreased stresses when DRCR < 1. Clinical Significance: This study highlights a potential mechanism to explain the high rates of failure of patellar OCAs. Additionally, the relationship between geometric features and stresses explored in this study led to a hypothetical scoring system that indicates which transplanted patellar grafts may have a higher risk of failure.

Osteochondral Allografts for Large Oval Defects of the Medial Femoral Condyle: A Comparison of Single Lateral Versus Medial Femoral Condyle Oval Grafts Versus 2 Overlapping Circular Grafts.

BACKGROUND: Studies have demonstrated the acceptability of using a contralateral nonorthotopic lateral femoral condyle (LFC) graft for a circular medial femoral condyle (MFC) osteochondral defect up to 20 to 25 mm in diameter. Larger oblong defects can now be managed using either overlapping circle grafts or a single oblong-shaped osteochondral allograft (OCA). PURPOSE: To determine if an oblong contralateral nonorthotopic LFC OCA can attain an acceptable surface contour match compared with an oblong ipsilateral MFC OCA or an overlapping circle technique for large oblong defects of the MFC. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 120 fresh-frozen human femoral condyles were matched by tibial width into 30 groups of 4 condyles (1 recipient MFC, 3 donor condyles). The recipient MFC was initially imaged using nano-computed tomography (nano-CT). A 17 × 36-mm oblong defect was created in the recipient MFC. Overall, 3 donor groups were formed: MFC oblong, LFC nonorthotopic oblong, LFC or MFC overlapping circles. After each transplant, the recipient condyle underwent nano-CT and was digitally reconstructed, which was superimposed on the initial nano-CT scan of the native recipient condyle. Dragonfly 3D software was used to determine the root mean square (RMS) of both the surface height deviation and the circumferential step-off height deviation between the native and donor cartilage surfaces for each graft. RESULTS: RMS surface height deviations were as follows: 0.59 mm for MFC oblong grafts, 0.58 mm for LFC oblong grafts, and 0.78 mm for overlapping circle grafts. The MFC and LFC oblong grafts had significantly less surface height deviation than the overlapping circle grafts (P = .004 and P = .002, respectively). RMS step-off height deviations were as follows: 0.68 mm for MFC oblong grafts, 0.70 mm for LFC oblong grafts, and 0.85 mm for overlapping circle grafts. The MFC and LFC oblong grafts had significantly less step-off height deviation than the overlapping circle grafts (P < .001 and P = .002, respectively). The majority of this difference was on the medial segment of the overlapping circle grafts. CONCLUSION: Oblong ipsilateral MFC OCAs and oblong contralateral nonorthotopic LFC OCAs produced a significantly better surface contour match to the native MFC than overlapping circle grafts for oblong defects 17 × 36 mm in size. CLINICAL RELEVANCE: Size-matched contralateral nonorthotopic LFC grafts are acceptable for MFC defects, which may allow for a quicker match, earlier patient care, and less wastage of valuable donor tissue.

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.

Factors Associated With Shoulder Activity Level at Time of Surgery and at 2-Year Follow-up in Patients Undergoing Shoulder Stabilization Surgery.

BACKGROUND: Patients undergoing shoulder stabilization surgery have been shown to have elevated activity levels. Factors associated with shoulder activity in this patient population at baseline and after surgery are unknown. HYPOTHESIS: Patient-specific variables are associated with shoulder activity level at baseline and at 2-year follow-up in a cohort of patients undergoing shoulder stabilization surgery. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Patients undergoing shoulder stabilization surgery were prospectively enrolled. As part of the data collection process, patients completed a previously validated Shoulder Activity Scale. A regression analysis was performed to assess the association of patient characteristics with baseline and 2-year follow-up shoulder activity levels. RESULTS: A total of 764 (n = 612 men, n = 152 women) out of 957 patients (80%) undergoing shoulder stabilization surgery with a median age of 25 years had baseline and 2-year follow-up data and were included in the current analysis. The baseline shoulder activity level was associated with race ( P < .0001) and preoperative duration of instability (P < .0001). At 2 years, 52% of the cohort had returned to the same or higher activity level after surgery. Predictors of higher shoulder activity level at 2-year follow-up included higher baseline activity level (P < .0001), male sex (P < .0001), younger age (P = .004), higher body mass index (BMI) (P = .03), more dislocations (P = .03), nonsmokers (P = .04), and race (P = .04). CONCLUSION: A longer duration of preoperative symptoms was associated with a lower baseline activity in this cohort. High baseline preoperative shoulder activity, younger age, male sex, higher BMI, number of dislocations, and nonsmoking status predicted higher shoulder activity 2 years after shoulder stabilization surgery. REGISTRATION: NCT02075775 (ClinicalTrials.gov identifier).

The Role of Mesenchymal Stromal Cells in the Management of Knee Chondral Defects.

➤: Mesenchymal stromal cells (MSCs) are a subset of progenitor cells that help to promote tissue healing and regeneration through the secretion of various cytokines and growth factors. Although technically pluripotent, MSCs in vivo rarely repair damaged tissue through direct differentiation and engraftment. ➤: Augmentation of traditional marrow stimulation techniques with MSCs has been theorized to improve repair tissue quality and defect fill. Clinical trials evaluating this technique are limited but have shown modest improvements compared with isolated marrow stimulation. ➤: Various scaffolds also have been utilized in combination with MSCs to treat focal chondral defects. Although the techniques described are heterogeneous, many have shown promising early clinical outcomes. ➤: Newer techniques involving 3-dimensional bioprinted scaffolds seeded with MSCs allow for the recreation of complex architecture, more closely resembling articular cartilage. These techniques are evolving and have not yet been studied in human clinical trials.

Editorial Commentary: Stabilize the Patella to Achieve Functional Gain but Don't Neglect the Cartilage That May Cause Long-Term Pain! Trochlear Dysplasia Plays a Role in Both.

While trochlear dysplasia is commonly discussed as a major risk factor for recurrent patellar instability, it also has a strong relationship with the development of patellofemoral cartilage lesions. Patellofemoral instability frequently occurs in teens and young adults, and the high prevalence of associated cartilage damage unfortunately sets patients up for the progression of degenerative changes of the patellofemoral joint at an early age. The judicious use of magnetic resonance imaging can help identify the presence of chondral lesions, allowing for urgent management of associated osteochondral fractures or open discussions and patient education about the possibility of performing a cartilage restoration procedure concurrently with patellar stabilization surgery. The location and presence of patellofemoral chondral lesions should be considered when contemplating the concurrent use of tibial tubercle osteotomy as part of the patellar stabilization procedure.

Beach Chair Versus Lateral Decubitus Position: Differences in Suture Anchor Position and Number During Arthroscopic Anterior Shoulder Stabilization.

BACKGROUND: Arthroscopic shoulder capsulolabral repair using glenoid-based suture anchor fixation provides consistently favorable outcomes for patients with anterior glenohumeral instability. To optimize outcomes, inferior anchor position, especially at the 6-o'clock position, has been emphasized. Proponents of both the beach-chair (BC) and lateral decubitus (LD) positions advocate that this anchor location can be consistently achieved in both positions. HYPOTHESIS: Patient positioning would be associated with the surgeon-reported labral tear length, total number of anchors used, number of anchors in the inferior glenoid, and placement of an anchor at the 6-o'clock position. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: This study was a cross-sectional analysis of a prospective multicenter cohort of patients undergoing primary arthroscopic anterior capsulolabral repair. Patient positioning in the BC versus LD position was determined by the operating surgeon and was not randomized. At the time of operative intervention, surgeon-reported labral tear length, total anchor number, anchor number in the inferior glenoid, and anchor placement at the 6-o'clock position were evaluated between BC and LD cohorts. Descriptive statistics and between-group differences (continuous: t test [normal distributions], Wilcoxon rank sum test [nonnormal distributions], and chi-square test [categorical]) were assessed. RESULTS: In total, 714 patients underwent arthroscopic anterior capsulolabral repair (BC vs LD, 406 [56.9%] vs 308 [43.1%]). The surgeon-reported labral tear length was greater for patients having surgery in the LD position (BC vs LD [mean ± SD], 123.5°± 49° vs 132.3°± 44°; P = .012). The LD position was associated with more anchors placed in the inferior glenoid and more frequent placement of anchors at the 6-o'clock (BC vs LD, 22.4% vs 51.6%; P < .001). The LD position was more frequently associated with utilization of ≥4 total anchors (BC vs LD, 33.5% vs 46.1%; P < .001). CONCLUSION: Surgeons utilizing the LD position for arthroscopic capsulolabral repair in patients with anterior shoulder instability more frequently placed anchors in the inferior glenoid and at the 6-o'clock position. Additionally, surgeon-reported labral tear length was longer when utilizing the LD position. These results suggest that patient positioning may influence the total number of anchors used, the number of anchors used in the inferior glenoid, and the frequency of anchor placement at the 6 o'clock position during arthroscopic capsulolabral repair for anterior shoulder instability. How these findings affect clinical outcomes warrants further study. REGISTRATION: NCT02075775 (ClinicalTrials.gov identifier).

Comparing the Efficacy of Kneeling Stress Radiographs and Weighted Gravity Stress Radiographs to Assess Posterior Cruciate Ligament Insufficiency.

BACKGROUND: Kneeling posterior cruciate ligament (PCL) stress radiographs are commonly used to evaluate PCL laxity. Patients, however, report significant pain, and the method's reproducibility may be challenged due to its dependence on patient body weight distribution to produce posterior tibial displacement. Weighted gravity stress radiography may offer better reproducibility and comfort than the kneeling technique, but its efficacy has not been studied. HYPOTHESIS: Weighted gravity PCL stress radiographs will be more comfortable and produce similar measurements of side-to-side difference in posterior tibial displacement when compared with the kneeling technique. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: A total of 40 patients with nonoperatively or >6 months postoperatively treated PCL injuries (isolated or multiligamentous) underwent bilateral stress radiographs. Weighted gravity and kneeling stress radiographs were acquired, in random order, for each patient, as well as side-to-side difference in posterior tibial displacement between each knee, patient-reported visual analog scale knee pain (100 mm), time to acquire the images, and patient preference for technique. Paired t tests were used to compare the side-to-side difference, pain score, and time to complete the radiographs. RESULTS: There was no difference between the 2 radiographic methods in the mean side-to-side difference (gravity: 6.45 ± 4.61 mm, kneeling: 6.82 ± 4.60 mm; P = .72), time required to acquire radiographs (kneeling: 307.3 ± 140.5 seconds, gravity: 318.7 ± 151.1 seconds; P = .073), or number of radiographs taken to obtain acceptable images (kneeling: 3.6 ± 1.6, gravity: 3.7 ± 1.7; P = .73). Patients reported significantly less knee pain during the weighted gravity views (kneeling: 31.8 ± 26.6, gravity: 4.0 ± 12.0; P < .0001). Of the patients, 88% preferred the weighted gravity method. CONCLUSION: Weighted gravity stress radiographs produce similar side-to-side differences in posterior tibial translation compared with the kneeling stress technique, but do not rely on patient weightbearing and provide significantly better patient comfort. Clinicians should therefore consider the use of weighted gravity stress radiographs in clinical practice to minimize the pain associated with stress radiography while allowing for accurate decision making.

Male Sex, Western Ontario Shoulder Instability Index Score, and Sport as Predictors of Large Labral Tears of the Shoulder: A Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability Cohort Study.

PURPOSE: To identify factors predictive of a large labral tear at the time of shoulder instability surgery. METHODS: As part of the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability cohort, patients undergoing open or arthroscopic shoulder instability surgery for a labral tear were evaluated. Patients with >270° tears were defined as having large labral tears. To build a predictive logistic regression model for large tears, the Feasible Solutions Algorithm was used to add significant interaction effects. RESULTS: After applying exclusion criteria, 1235 patients were available for analysis. There were 222 females (18.0%) and 1013 males (82.0%) in the cohort, with an average age of 24.7 years (range 12 to 66). The prevalence of large tears was 4.6% (n = 57), with the average tear size being 141.9°. Males accounted for significantly more of the large tears seen in the cohort (94.7%, P = .01). Racquet sports (P = .01), swimming (P = .02), softball (P = .05), skiing (P = .04), and golf (P = .04) were all associated with large labral tears, as was a higher Western Ontario Shoulder Instability Index (WOSI; P = .01). Age, race, history of dislocation, and injury during sport were not associated with having a larger tear. Using our predictive logistic regression model for large tears, patients with a larger body mass index (BMI) who played contact sports were also more likely to have large tears (P = .007). CONCLUSIONS: Multiple factors were identified as being associated with large labral tears at the time of surgery, including male sex, preoperative WOSI score, and participation in certain sports including racquet sports, softball, skiing, swimming, and golf. LEVEL OF EVIDENCE: I, prognostic study.

Relationship between Anatomical Risk Factors, Articular Cartilage Lesions, and Patient Outcomes Following Medial Patellofemoral Ligament Reconstruction.

OBJECTIVE: The purpose of this study was (1) to determine which risk factors for patellar instability were associated with the presence of patellofemoral cartilage lesions and (2) to determine how cartilage lesion presence, size, and grade affect postoperative disease-specific quality of life. DESIGN: Preoperative, intraoperative, and postoperative demographic, anthropometric (body mass index, Beighton score, hip rotation), radiographic (crossover sign, trochlear bump), cartilage lesion morphology (presence, size, location, grade), and outcomes data (Banff Patella Instability Instrument 2.0 [BPII 2.0]) were prospectively collected from patients undergoing isolated medial patellofemoral ligament reconstruction. For all knees (n = 264), single and multivariable logistic regression was used to determine if any patellar instability risk factors affected the odds of having a cartilage lesion. In patients with unilateral symptoms (n = 121), single variable linear regression was used to determine if the presence, size, or ICRS (International Cartilage Regeneration & Joint Preservation Society) grade of cartilage lesions could predict the 12 or 24+ month postoperative BPII 2.0 score. RESULTS: A total of 84.5% of knees had patellofemoral cartilage lesions (88.3% involved the distal-medial patella). Trochlear dysplasia (high grade: odds ratio = 15.7, P < 0.001; low grade: odds ratio = 2.9, P = 0.015) was associated with the presence of a cartilage lesion. The presence, size, and grade of cartilage lesions were not associated with 12 or 24+ month postoperative BPII 2.0 scores. CONCLUSIONS: Trochlear dysplasia was a risk factor for the development of patellofemoral cartilage lesions in this patient population. Cartilage lesions most commonly involve the distal-medial patella. There was no significant relationship between patellofemoral cartilage lesion presence, size, or grade and postoperative BPII 2.0 scores in short-term follow-up.

Does the Symmetry of Patellar Morphology Matter When Matching Osteochondral Allografts for Osteochondral Defects Involving the Central Ridge of the Patella?

OBJECTIVE: The purpose of this study was to determine if differences in Wiberg classification play a role in the ability of donor patellar osteochondral allografts to match the native patellar surface when treating osteochondral defects of the patellar apex. DESIGN: Twenty (10 Wiberg I and 10 Wiberg II/III) human patellae were designated as the recipient. Each recipient was size-matched to both a Wiberg I and a Wiberg II/III patellar donor. A 16-mm circular osteochondral "defect" was created on the central ridge of the recipient patella. The 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 (computed tomography) scanned, digitally reconstructed, registered to the initial nano-CT scan of the recipient patella, and processed to determine root mean squared circumferential step-off heights as well as surface height deviation. The process was then repeated for the other allograft plug. RESULTS: There was no significant difference in mean step-off height between matched and unmatched Wiberg plugs; however, there was a statistically significant difference in surface height deviation over the whole surface (0.50 mm and 0.64 mm respectively, P = 0.03). This difference of 0.14 mm is not felt to be clinically significant. Tibial width was correlated to patellar width (r = 0.82) and patellar height (r = 0.68). CONCLUSIONS: For osteochondral allograft sizes up to 16 mm there appears to be no advantage to match donor and recipient patellar morphology. Further study is warranted to evaluate defects requiring larger graft sizes.

Safety and early results of Subchondroplasty® for the treatment of bone marrow lesions in osteoarthritis: a systematic review.

PURPOSE: Subchondroplasty® is a novel minimally invasive procedure for painful subchondral bone marrow lesions (BMLs). The aim of this systematic review was to characterize the clinical outcomes of the Subchondroplasty® procedure, a novel minimally invasive procedure for the treatment of BMLs. The hypothesis tested was that patients experience improvements in pain and functional outcomes following the Subchondroplasty® procedure. METHODS: MEDLINE, Embase, Web of Science, and Clinicaltrials.gov were searched from database inception to search date (June 10, 2020) for all clinical studies which discussed Subchondroplasty®. Two reviewers independently screened 45 unique results and 17 studies were included in the final analysis. Data were collected regarding patient demographics, indications, pain, functional scores, conversion to TKA, and complications of the procedure. RESULTS: All but one study were level IV evidence; the mean MINORS score was 9 ± 2. There were 756 patients included, 45.1% were female, and the mean age was 54 years (range 20-85). Thirteen studies investigated the effect Subchondroplasty® to the knee, while four studied the impact on the foot and ankle. Median length of follow-up was 12 months. The most common indication for Subchondroplasty® was joint pain with corresponding BML. Major contraindications to Subchondroplasty® included severe OA, joint instability, and malalignment. Mean pain score on visual analogue scale (VAS) prior to Subchondroplasty® was 7.8 ± 0.6, but decreased to 3.4 ± 0.7 postoperatively. All studies investigating functional scores reported improvement following Subchondroplasty® (IKDC 31.7 ± 1.9-54.0 ± 4.2 and KOOS 38.1 ± 0.6-70.0 ± 4.1). There were consistently high levels of patient satisfaction; 87 ± 8% of patients would be willing to undergo the procedure again. Seven cases of complications were reported, most seriously osteomyelitis and avascular necrosis. Conversion to knee arthroplasty ranged from 12.5 to 30% with length of follow-up ranging from 10 months to 7 years. CONCLUSIONS: Existing low-quality studies show Subchondroplasty® to benefit patients with BMLs through reduction in pain and improvement in function, along with a high degree of satisfaction following the procedure. The low short-to-medium term conversion rate to arthroplasty suggests that Subchondroplasty® may play a role in delaying more invasive and expensive procedures in patients with BMLs. Subchondroplasty® is a novel procedure that has promising initial findings, but requires further high-quality, comparative studies with long-term follow-up to better understand the outcomes of the procedure and impact clinical practice recommendations. LEVEL OF EVIDENCE: Systematic Review of Level III and IV Studies, Level IV.

Effect of a brief scenario-tailored educational program on parents' risk knowledge, perceptions, and decisions to administer prescribed opioids: a randomized controlled trial.

ABSTRACT: This randomized, controlled trial evaluated whether a brief educational program (ie, Scenario-Tailored Opioid Messaging Program [STOMP]) would improve parental opioid risk knowledge, perceptions, and analgesic efficacy; ensure safe opioid use decisions; and impact prescription opioid use after surgery. Parent-child dyads (n = 604) who were prescribed an opioid for short-term use were randomized to routine instruction (Control) or routine plus STOMP administered preoperatively. Baseline and follow-up surveys assessed parents' awareness and perceived seriousness of adverse opioid effects, and their analgesic efficacy. Parents' decisions to give an opioid in hypothetical scenarios and total opioid doses they gave to children at home were assessed at follow-up. Scenario-Tailored Opioid Messaging Program parents gained enhanced perceptions of opioid-related risks over time, whereas Controls did not; however, risk perceptions did not differ between groups except for addiction risk. Scenario-Tailored Opioid Messaging Program parents exhibited marginally greater self-efficacy compared to Controls (mean difference vs controls = 0.58 [95% confidence interval 0.08-1.09], P = 0.023). Scenario-Tailored Opioid Messaging Program parents had a 53% lower odds of giving an opioid in an excessive sedation scenario (odds ratio 0.47 [95% confidence interval 0.28-0.78], P = 0.003), but otherwise made similar scenario-based opioid decisions. Scenario-Tailored Opioid Messaging Program was not associated with total opioid doses administered at home. Instead, parents' analgesic efficacy and pain-relief preferences explained 7%, whereas child and surgical factors explained 22% of the variance in opioid doses. Scenario-tailored education enhanced parents' opioid risk knowledge, perceptions, and scenario-based decision-making. Although this may inform later situation-specific decision-making, our research did not demonstrate an impact on total opioid dosing, which was primarily driven by surgical and child-related factors.

Risk Factors for Intra-articular Bone and Cartilage Lesions in Patients Undergoing Surgical Treatment for Posterior Instability.

BACKGROUND: Patients with posterior shoulder instability may have bone and cartilage lesions (BCLs) in addition to capsulolabral injuries, although the risk factors for these intra-articular lesions are unclear. HYPOTHESIS: We hypothesized that patients with posterior instability who had a greater number of instability events would have a higher rate of BCLs compared with patients who had fewer instability episodes. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Data from the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Group instability patient cohort were analyzed. Patients aged 12 to 99 years undergoing primary surgical treatment for shoulder instability were included. The glenohumeral joint was evaluated by the treating surgeon at the time of surgery, and patients were classified as having a BCL if they had any grade 3 or 4 glenoid or humeral cartilage lesion, reverse Hill-Sachs lesion, bony Bankart lesion, or glenoid bone loss. The effects of the number of instability events on the presence of BCLs was investigated by use of Fisher exact tests. Logistic regression modeling was performed to investigate the independent contributions of demographic variables and injury-specific variables to the likelihood of having a BCL. Significance was defined as P < .05. RESULTS: We identified 271 patients (223 male) for analysis. Bone and cartilage lesions were identified in 54 patients (19.9%) at the time of surgical treatment. A glenoid cartilage injury was most common and was identified in 28 patients (10.3%). A significant difference was noted between the number of instability events and the presence of BCLs (P = .025), with the highest rate observed in patients with 2 to 5 instability events (32.3%). Multivariate logistic regression modeling indicated that increasing age (P = .019) and 2 to 5 reported instability events (P = .001) were significant independent predictors of the presence of BCLs. For bone lesions alone, the number of instability events was the only significant independent predictor; increased risk of bone lesion was present for patients with 1 instability event (OR, 6.1; P = .012), patients with 2 to 5 instability events (OR, 4.2; P = .033), and patients with more than 5 instability events (OR, 6.0; P = .011). CONCLUSION: Bone and cartilage lesions are seen significantly more frequently with increasing patient age and in patients with 2 to 5 instability events. Early surgical stabilization for posterior instability may be considered to potentially limit the extent of associated intra-articular injury. The group of patients with more than 5 instability events may represent a different pathological condition, as this group showed a decrease in the likelihood of cartilage injury, although not bony injury.

Contralateral Lateral Femoral Condyle Allografts Provide an Acceptable Surface Match for Simulated Classic Osteochondritis Dissecans Lesions of the Medial Femoral Condyle.

BACKGROUND: Osteochondral allograft transplantation is an effective technique for repairing large lesions of the medial femoral condyle (MFC), but its use is limited by graft availability. PURPOSE/HYPOTHESIS: The present study aimed to determine whether contralateral lateral femoral condyle (LFC) allografts can provide an acceptable surface match for posterolateral MFC lesions characteristic of classic osteochondritis dissecans (OCD). The hypothesis was that LFC and MFC allografts will provide similar surface contour matches in all 4 quadrants of the graft for posterolateral MFC lesions characteristic of OCD. STUDY DESIGN: Controlled laboratory study. METHODS: Ten fresh-frozen recipient human MFCs were each size-matched to 1 ipsilateral medial and 1 contralateral LFC donor (N = 30 condyles). After a nano-computed tomography (nano-CT) scan of the native recipient condyle, a 20-mm circular osteochondral "defect" was created 1 cm posterior and 1 cm medial to the roof of the intercondylar notch (n = 10). A size-matched, random-order donor MFC or LFC plug was then harvested, transplanted, and scanned with nano-CT. Nano-CT scans were then reconstructed, registered to the initial scan of the recipient MFC, and processed in MATLAB to determine the height deviation (d RMS) between the native and donor surfaces and percentage area unacceptably (>1 mm) proud (%A proud) and sunken (%A sunk). Circumferential step-off height (h RMS) and percentage circumference unacceptably (>1 mm) proud (%C proud) and sunken (%C sunk) were measured using DragonFly software. The process was then repeated for the other allograft plug. RESULTS: Both MFC and LFC plugs showed acceptable step-off heights in all 4 quadrants (range, 0.53-0.94 mm). Neither allograft type nor location within the defect had a significant effect on step-off height (h RMS), surface deviation (d RMS), %A proud, or %A sunk. In general, plugs were more unacceptably sunken than proud (MFC, 13.4% vs 2.4%; LFC, 13.2% vs 8.1%), although no significant differences in %C sunk were seen between allograft types or locations within the defect. In LFC plugs, %C proud in the lateral quadrant (28.0% ± 26.1%) was significantly greater compared with all other quadrants (P = .0002). CONCLUSION: The present study demonstrates that 20-mm contralateral LFC allografts provide an acceptable surface match for posterolateral MFC lesions characteristic of OCD. CLINICAL RELEVANCE: With comparable surface matching, MFC and LFC allografts can be expected to present similar stresses on the knee joint and achieve predictably positive clinical outcomes, thus improving donor availability and reducing surgical wait times for matches.