Biologic Augmentation during Meniscal Repair

We reviewed the literature regarding utility of biologic augmentation in meniscal repair. We hypothesized that the addition of biologic augmentation during meniscal repair improves postoperative knee function and reduces risk of repair failure. PubMed and Embase databases were systematically searched. Included studies were clinical studies in humans, published in English, and reported use of biologic augmentation techniques in addition to meniscal repair (including platelet-rich plasma [PRP], fibrin clot, bone marrow stimulation, meniscal wrapping, and bioscaffolds) for treatment of knee meniscal tears. Outcome measures included repair failure, repeat knee arthroscopic surgery, and magnetic resonance imaging), visual analog scale for pain, the International Knee Documentation Committee questionnaire, the Western Ontario and McMaster Universities Osteoarthritis Index Lysholm's Knee Scoring Scale, and the Knee Injury and Osteoarthritis Outcome Score. Study quality was assessed using the modified Coleman methodology score. Nineteen studies reported repair of 1,092 menisci including six studies that investigated fibrin clot augmentation, five studies that investigated PRP augmentation, three studies that investigated bone marrow stimulation augmentation, two studies that used meniscal wrapping augmentation, and three studies that used other techniques. The level of evidence ranged from I to IV and mean modified Coleman methodology score was 43 (range: 17–69), with higher scores noted in studies completed in recent years. PRP and bone marrow stimulation augmentation appear to decrease risk of failure in patients undergoing isolated meniscal repair but do not improve knee symptom scores. Fibrin clot and trephination augmentation techniques do not have sufficient evidence to support decreased failure risk at this time. Meniscal wrapping augmentation and scaffold implantation augmentation appear to be an attractive option to meniscectomy in complicated tears that are not candidates for repair alone, but further confirmatory studies are needed to support initial data. Evidence supporting augmentation of meniscal repair is limited at this time but suggests that the highest likelihood for effectiveness of augmentation is in the settings of isolated meniscal repair or meniscal repairs that would normally not be amenable to repair.

Impact of Early Weightbearing After Ankle Arthroscopy and Bone Marrow Stimulation for Osteochondral Lesions of the Talus

Background: Osteochondral lesion of the talus (OLT) may be caused by osteochondritis dissecans, osteochondral fractures, avascular necrosis, or focal arthritic changes. For certain focal cartilage defects, bone marrow stimulation (BMS) has been a widely used technique to restore a fibrocartilage substitute overlying the defect. There are various postoperative weightbearing protocols for this procedure, with no single gold standard method. Purpose: To retrospectively review the outcomes of patients undergoing ankle arthroscopy with concomitant BMS to determine outcomes based on postoperative weightbearing status. Study Design: Cohort study; Level of evidence, 3. Methods: We retrospectively reviewed the records of patients who underwent ankle arthroscopy with BMS for OLTs between 2015 and 2018. Patients were placed into 2 cohorts based on postoperative immobilization status: the nonweightbearing (NWB) group and the weightbearing-as-tolerated (WBAT) group. Patient characteristics obtained included age, sex, comorbidities, and etiology of talar pathology. Outcomes included the pain visual analog scale (VAS), range of motion (ROM), complications, time to first weightbearing, and the method and length of immobilization. Patients who were lost to follow-up before 30 days were excluded. The chi-square test was used to compare categorical variables between cohorts, and the t test was used for continuous variables. Results: A total of 69 patients met the inclusion criteria for this study, 18 in the WBAT group and 51 in the NWB group. The mean lesion size was 9.48 × 9.21 mm (range, 3-15 mm × 2-20 mm) for the NWB group and 9.36 × 9.72 mm (range, 5-14 mm × 6-20 mm) for the WBAT group ( P > .05). The VAS scores improved from 4.40 to 0.67 for the WBAT group and from 6.33 to 2.55 for the NWB group, with the difference in final values reaching statistical significance ( P = .0002). Postoperative ROM was not significantly different between the groups. There were 4 repeat operations within the NWB cohort. Conclusion: The surgical management of OLTs can be challenging, and the postoperative weightbearing protocol can be an extra obstacle for the patient to navigate. We found no difference in pain, ROM, or complications when allowing immediate, full WBAT.

Prior Bone Marrow Stimulation Surgery Influences Outcomes After Cell-Based Cartilage Restoration: A Systematic Review and Meta-analysis

Background: Cell-based cartilage restoration with autologous chondrocyte implantation (ACI) is a safe and effective treatment for symptomatic cartilage lesions. Many patients undergoing ACI have a history of prior surgery, including bone marrow stimulation (BMS). There is mounting evidence that a history of prior BMS may impede healing of the ACI graft. Purpose/Hypothesis: The purpose of this study was to compare the failure rates of primary ACI with ACI after prior BMS. We hypothesized that ACI after BMS would have a significantly higher failure rate (defined as reoperation, conversion to arthroplasty, and/or imaging-based failure) compared with primary ACI. Study Design: Systematic review; Level of evidence, 4. Methods: A literature search was performed by use of PubMed and Embase databases for relevant articles published through October 2, 2020, to identify studies evaluating outcomes and failures rates of ACI after prior BMS in the knee. Results: Included were 11 studies comprising 1479 ACI procedures. The mean age at surgery ranged from 18.3 to 39.1 years, and the mean follow-up ranged from 3 to 20.6 years. All studies reported failure rates. The overall failure rate was significantly higher in the patients who underwent ACI after BMS, at 26.4% compared with 14.8% in the ACI group ( P < .001). Meta-analysis demonstrated an increased risk of failure in patients with a history of prior BMS (log odds ratio = –0.90 [95% confidence interval, –1.38 to –0.42]). Conclusion: This systematic review demonstrated that failure rates were significantly higher for patients treated with ACI after BMS relative to patients undergoing ACI without prior BMS. This finding has important implications when considering the use of BMS for defects that are amenable to cell-based restoration and when determining treatment options after failed BMS. Registration: PROSPERO (CRD42020180387).

Mesenchymal Stem Cell Extracellular Vesicles as Adjuvant to Bone Marrow Stimulation in Chondral Defect Repair in a Minipig Model

Objective This study evaluated the effects of mesenchymal stem cell-extracellular vesicles (MSC-EVs) on chondrocyte proliferation in vitro and on cartilage repair in vivo following bone marrow stimulation (BMS) of focal chondral defects of the knee. Methods Six adult Göttingen minipigs received 2 chondral defects in each knee. The pigs were randomized to treatment with either BMS combined with MSC-EVs or BMS combined with phosphate-buffered saline (PBS). Intraarticular injections MSC-EVs or PBS were performed immediately after closure of the surgical incisions, and at 2 and 4 weeks postoperatively. Repair was evaluated after 6 months with gross examination, histology, histomorphometry, immunohistochemistry, and micro-computed tomography (µCT) analysis of the trabecular bone beneath the defect. Results Defects treated with MSC-EVs had more bone in the cartilage defect area than the PBS-treated defects (7.9% vs. 1.5%, P = 0.02). Less than 1% of the repair tissue in both groups was hyaline cartilage. International Cartilage and Joint Preservation Society II histological scoring showed that defects treated with MSC-EVs scored lower on “matrix staining” (20.8 vs. 50.0, P = 0.03), “cell morphology” (35.4 vs. 53.8, P = 0.04), and “overall assessment” (30.8 vs. 52.9, P = 0.03). Consistently, defects treated with MSC-EVs had lower collagen II and higher collagen I areal deposition. Defects treated with MSC-EVs had subchondral bone with significantly higher tissue mineral densities than PBS-treated defects (860 mg HA/cm3 vs. 838 mg HA/cm3, P = 0.02). Conclusion Intraarticular injections of MSC-EVs in conjunction with BMS led to osseous ingrowth that impaired optimal cartilage repair, while enhancing subchondral bone healing.

CLINICAL OUTCOMES OF OPERATIVE MANAGEMENT OF CAPITELLAR OSTEOCHONDRITIS DISSECANS IN ADOLESCENT ATHLETES

Background: Capitellar osteochondritis dissecans (OCD) is commonly encountered in youth athletes. There are limited reports on long term outcomes using validated outcome scores following surgical treatment of elbow OCD in adolescents. Purpose: To examine the outcomes of operative treatment of elbow OCD in adolescent athletes and investigate return to sport rate as well as athletic and daily function. Methods: 17 adolescent athletes (average age 14.2 ± 1.5 years) and 18 elbows with OCD treated arthroscopically were retrospectively reviewed. The average duration of symptoms prior to surgery was 15.4 ± 12.5 months and average follow up was 4.4 ± 3.7 years. Data points examined included pre-operative lesion grade/size, range of motion (ROM), and bone age; intra-operative lesion grade/size; and post-operative ROM, Kerlan-Jobe Orthopaedic Clinic (KJOC) Overhead Athlete Shoulder and Elbow score, and Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) score. Results: All patients were treated with initial diagnostic arthroscopy. 14/17 patients were definitively treated with arthroscopic debridement and marrow stimulation/microfracture. 3/17 patients required open treatment with two patients amendable to osteochondral fixation and one patient to open marrow stimulation/microfracture. 14/17 athletes returned to their sport post-operatively with 12/17 returning to the same level or higher, and 2/17 returning to a lower level of recreational play. 3/17 athletes did not return to sports but advised that this was by choice not due to their elbow OCD. Overall, there were significant improvements in elbow ROM post-operatively as well as excellent QuickDASH (average 1.9 ± 4.4) and KJOC scores (average 93 ± 8.0) seen amongst all athletes. There was no correlation between pre-operative lesion grade/size, bone age, or open versus arthroscopic treatment with outcome. Conclusion: Operative treatment of elbow OCD in adolescent athletes not only leads to high return to sports rates but also high levels of athletic and daily functional activity long term.