Platelet-rich plasma augmentation in anterior cruciate ligament reconstruction: Evidence is still too scattered. A scoping review of randomised controlled trials

PURPOSE

Platelet-rich plasma (PRP) augmentation has been proposed to improve the results of anterior cruciate ligament reconstruction (ACLR). The present study aims to quantify the available evidence to support the use of PRP as biological augmentation in ACLR surgery.

METHODS

A systematic literature search was conducted on the PubMed, Cochrane, Web of Science and Embase databases on 10 March 2023. Inclusion criteria were randomised controlled trials (RCTs), written in English, addressing PRP augmentation in ACLR surgery, with no time limitation. A scoping review was performed to map the body of literature by examining the evidence related to specific aspects of patients' treatment and evaluation. Risk of bias evaluation was performed with the Cochrane risk-of-bias tool for randomised trials Version 2 (RoB 2), while the quality assessment was performed with the use of the Coleman Score.

RESULTS

Out of 983 articles retrieved, 23 RCTs on 943 knees were included in this scoping review. PRP was administered in a liquid form in nine studies and clotted in 11 studies, while in three studies both liquid and clotted PRP were used. Hamstring auto/allografts were used in 14 studies, patellar tendon auto/allografts were used in eight studies and one study described ACLR with peroneus longus allografts. The map of the evidence documented high heterogeneity also in terms of surgical technique, objective and subjective outcome measures and radiological assessment, as well as follow-up times ranging from 1 day to 2 years, with virtually no overlapping data among studies neither in terms of treatments nor evaluations. Risk of bias evaluation showed an overall low quality of the included studies.

CONCLUSIONS

The available literature addressing PRP augmentation in ACLR is largely scattered. PRP was produced and applied following different procedures, and high variability was detected across the included studies for every aspect of ACLR surgery and evaluation. Currently, a meaningful comparison of the available studies is not possible as the quantification of the literature results is biased by their heterogeneity. Future studies should provide more standardisation to investigate the benefits of biological augmentation in ACL surgery and confirm the promising yet weak evidence of PRP potential as well as the most suitable application modality, before routine use in clinical practice.

LEVEL OF EVIDENCE

Levels I and II, scoping review.

Intra-articular corticosteroid injections provide a clinically relevant benefit compared to placebo only at short-term follow-up in patients with knee osteoarthritis: A systematic review and meta-analysis

PURPOSE

To quantify the clinical relevance of intra-articular corticosteroid effects compared to placebo for the injective treatment of knee osteoarthritis (OA).

METHODS

The PubMed, Cochrane Library and Web of Science databases were searched on May 3, 2023. This study was conducted in accordance with the PRISMA guidelines. The inclusion criteria were randomized controlled trials (RCTs), published in English, with no time limitation regarding publication date, comparing intra-articular corticosteroids and placebo injections for knee OA. The effects were quantified at short- (≤6 weeks), mid- (>6 weeks and ≤3 months), and long-term (≥6 months) follow-ups. The minimal clinically important difference (MCID) for the outcomes (visual analogue scale for pain - VAS: 1.4, Western Ontario and McMaster University Osteoarthritis Index - WOMAC: 9) was used to interpret the clinical improvement provided by intra-articular corticosteroid injections compared to placebo. The quality of each article was assessed using the Cochrane RoB 2 tool and the GRADE guidelines.

RESULTS

Among the 1030 articles retrieved, 11 RCTs (842 patients) were included. A comparison of the two groups revealed statistically significant differences in the improvement of VAS and WOMAC scores in terms of the mean difference (MD); this difference was in favour of corticosteroids at short-term (p < 0.001, MD = -1.6 and p < 0.001, MD = -9.9, respectively) and mid-term follow-ups (p = 0.001, mean MD = -1.3 and p = 0.005, MD = -4.9, respectively). No difference was observed at the long-term follow-up. The MDs between the improvements in the two groups reached the MCID values for the VAS and WOMAC only at the short-term follow-up. The RoB 2 tool and the GRADE evaluations showed the presence of risk of bias and limited quality of evidence.

CONCLUSION

This systematic review and meta-analysis demonstrated that intra-articular corticosteroid injections offer clinically perceivable pain relief and functional improvement higher than the placebo effect only at short-term follow-up in patients affected by knee OA, with benefits losing clinical relevance already after 6 weeks. These results, together with the low number and the limited quality of the RCTs comparing this treatment with placebo, question the indication for the use of corticosteroid injections in clinical practice for the treatment of knee OA.

LEVEL OF EVIDENCE

Level I.

Medial meniscal lesions increase antero-posterior laxity in knees with anterior cruciate ligament injury

PURPOSE

The aim of this study was to quantify the impact of concomitant meniscal lesions on knee laxity using a triaxial accelerometer in a large population of patients affected by anterior cruciate ligament (ACL) injury.

METHODS

A total of 326 consecutive patients (261 men and 65 women, mean age 31.3 ± 11.3) undergoing primary ACL reconstruction, were preoperatively evaluated through Lachman and pivot shift tests using a triaxial accelerometer to quantify knee laxity. An analysis based on the presence of meniscal tears assessed during surgery was performed to evaluate the impact of meniscal lesions on knee laxity.

RESULTS

The anterior tibial translation (Lachman test) presented significantly higher values in patients with medial meniscal lesions (7.3 ± 1.7 mm, p = 0.049) and both medial and lateral meniscal lesions (7.7 ± 1.6 mm, p = 0.001) compared to patients without concomitant meniscal lesions (6.7 ± 1.3 mm). Moreover, patients with both medial and lateral meniscal lesions presented significantly higher values of anterior tibial translation compared to patients with lateral meniscal lesions (p = 0.049). No statistically significant differences were found between the groups in terms of tibial acceleration (pivot shift test).

CONCLUSION

This study demonstrated that the contribution of concomitant meniscal lesions to knee laxity can be objectively quantified using a triaxial accelerometer in ACL-injured knees. In particular, medial meniscus lesions, alone or in association with lateral meniscus lesions, determine a significant increase of the anterior tibial translation compared to knees without meniscus tears.

LEVEL OF EVIDENCE

Level IV.

The reimbursement system can influence the treatment choice and favor joint replacement versus other less invasive solutions in patients affected by osteoarthritis

PURPOSE

The aim of this study was to assess how physicians perceive the role of the reimbursement system and its potential influence in affecting their treatment choice in the management of patients affected by osteoarthritis (OA).

METHODS

A survey was administered to 283 members of SIAGASCOT (Italian Society of Arthroscopy, Knee, Upper Limb, Sport, Cartilage and Orthopaedic Technologies), a National scientific orthopaedic society. The survey presented multiple choice questions on the access allowed by the current Diagnosis-Related Groups (DRG) system to all necessary options to treat patients affected by OA and on the influence toward prosthetic solutions versus other less invasive options.

RESULTS

Almost 70% of the participants consider that the current DRG system does not allow access to all necessary options to best treat patients affected by OA. More than half of the participants thought that the current DRG system favors the choice of prosthetic solutions (55%) and that it can contribute to the increase in prosthetic implantation at the expense of less invasive solutions (54%). The sub-analyses based on different age groups, professional roles, and places of work allowed to evaluate the response in each specific category, confirming the findings for all investigated aspects.

CONCLUSIONS

This survey documented that the majority of physicians consider that the reimbursement system can influence the treatment choice when managing OA patients. The current DRG system was perceived as unbalanced in favor of the choice of the prosthetic solution, which could contribute to the increase in prosthetic implantation at the expense of other less invasive options for OA management.

Adipose Tissue-Derived Minimally Manipulated Products versus Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis: A Systematic Review of Clinical Evidence and Meta-Analysis

The use of minimally manipulated adipose tissue (MM-AT) products is gaining increasing interest for the treatment of knee osteoarthritis (OA). MM-AT represents an easy way to exploit adipose tissue properties, although clinical evidence is still limited, as well as their benefits with respect to more documented orthobiologics like platelet-rich plasma (PRP). A systematic review and meta-analysis were performed to evaluate the safety and efficacy of MM-AT products for knee OA management. The risk of bias of the included studies was evaluated using the Dawns and Black checklist for all the included studies and RoB-2.0 for randomized controlled trials (RCTs). Thirty-three clinical studies were included in the qualitative analysis: 13 prospective case series, 10 retrospective case series, 7 RCTs, 2 retrospective comparative studies, and 1 prospective comparative study. An overall clinical improvement and few minor adverse events were observed. Five RCTs comparing MM-AT and PRP injections were meta-analyzed, showing comparable results. The analysis also highlighted the limits of the literature, with only a few high-level trials and an overall low quality. Even though the current literature is still limited, the available evidence suggests the safety and overall positive results of the intra-articular injections of MM-AT products for knee OA treatment.

Intra-articular injections in sport-active patients with degenerative cartilage lesions or osteoarthritis of the knee: a systematic review

PURPOSE

The aim of this systematic review was to analyse the available clinical evidence on intra-articular knee injections for the treatment of degenerative cartilage lesions and osteoarthritis (OA) in sport-active patients.

METHODS

A literature search was performed in July 2023 according to the PRISMA guidelines on three electronic databases (PubMed, Cochrane, Web of Science). Studies addressing intra-articular injections for degenerative knee cartilage lesions or knee OA in sport-active patients were included. The Downs and Black's "checklist for measuring quality" was used to evaluate risk of bias and quality of the included studies.

RESULTS

Only 10 clinical studies for a total of 296 sport-active patients were included, with a publication trend increasing over time. The studies were 9 case series and 1 RCT; 7 studies focused on hyaluronic acid (HA), 2 studies focused on platelet-rich plasma (PRP), while 1 study compared HA and PRP. Overall, safety and positive clinical findings were for both HA and PRP, although not always with satisfactory results in terms of return to sport. The Downs and Black evaluation showed an overall poor quality of the included studies, with an average score of 21.1 points (range 19-25).

CONCLUSIONS

The available clinical evidence is still limited, with only a few studies published and an overall low-quality of evidence, suggesting a potential role of HA and PRP injections to treat these patients. However, further high-level trials are needed to confirm the real benefits of these treatments for the management of sport-active patients affected by degenerative cartilage lesions or OA of the knee.

The 'placebo effect' in the conservative treatment of plantar fasciitis: a systematic review and meta-analyses

Purpose

The study of the placebo effect is key to elucidate the 'real effect' of conservative interventions for plantar fasciitis. The aim of this meta-analysis was to quantify the impact of placebo in the different conservative treatments of plantar fasciitis.

Methods

A systematic literature review was performed on double-blind placebo-controlled trials (RCTs) according to PRISMA guidelines on PubMed, Embase, and Web of Science. The meta-analysis primary outcome was the 0-10 pain variation after placebo treatments analyzed at 1 week, 1, 3, 6, and 12 months. The risk of bias was assessed using the RoB 2.0 tool, while the overall quality of evidence was graded according to the GRADE guidelines.

Results

The placebo effect for conservative treatments was studied in 42 double-blind RCTs on 1724 patients. The meta-analysis of VAS pain showed a statistically significant improvement after placebo administration of 2.13/10 points (P < 0.001), being highest at 12 months with 2.79/10 points (P < 0.001). The improvement of the placebo groups was higher in the extracorporeal shock wave therapy studies compared to the injection studies (2.59 vs 1.78; P = 0.05). Eight studies had a low risk of bias, 23 studies had 'some concerns,' and 4 studies had a high risk of bias. The GRADE evaluation showed an overall high quality of evidence.

Conclusion

This systematic review and meta-analysis demonstrated that the placebo effect represents an important component of all conservative approaches to treat plantar fasciitis. This effect is statistically and clinically significant, increases over time, and depends on the type of conservative treatment applied to address plantar fasciitis.

Hyaluronic scaffold transplantation with bone marrow concentrate for the treatment of osteochondral lesions of the talus: durable results up to a minimum of 10 years

PURPOSE

The aim of this study was to evaluate the long-term clinical results of the transplantation of a hyaluronic acid membrane augmented with bone marrow aspirate concentrate (BMAC) in an one-step technique for the treatment of patients affected by osteochondral lesions of the talus (OLT).

METHODS

A total of 101 patients (64 men, 37 women, age 32.9 ± 10.9) were evaluated for a minimum of 10 years of follow-up (151.5 ± 18.4 months) The mean lesion size was 2.2 ± 1.4 cm2, the lesion had a post-traumatic origin in 73 patients, 15 patients previously had an ankle fracture, 22 patients had ankle osteoarthritis. All patients were clinically evaluated at baseline and at 2, 5, and a minimum of 10 years after treatment using the AOFAS score, the NRS for pain, and the Tegner score. A survival analysis was performed to check the survival to failure up to the last follow-up.

RESULTS

The AOFAS score significantly improved from baseline (59.6 ± 13.9) to the final follow-up (82.3 ± 14.2) (p < 0.0005). A significant reduction in the AOFAS score was found from 2 to 10 years (p < 0.0005). The NRS for pain changed from 7.0 ± 1.3 at baseline to 3.9 ± 2.7 at the final follow-up (p < 0.0005). A significant worsening was documented between 5 years and the final follow-up (p < 0.0005). The Tegner score improved from the preoperative value of 2.0 (range 1-7) to 3.0 (range 1-7) at the final follow-up (p < 0.0005), although it remained lower as compared to the preinjury level of 4.0 (range 1-9) (p < 0.0005). Better results were documented in male and younger patients with smaller lesions, without the previous surgery, and without the previous ankle fractures or osteoarthritis. At the final follow-up, 85 patients considered their general health status "satisfactory" and 84 patients reported feeling "better" than the preoperative condition. Five patients were considered failures and underwent prosthetic ankle replacement or repeated the same surgery.

CONCLUSION

This one-step technique showed to be an effective procedure for the treatment of OLT, providing a low failure rate and offering durable clinical improvements up to a minimum of 10 years of follow-up. However, this technique demonstrated a small yet significant decrease over the years in terms of pain and function and poor results in terms of sports activity level.

LEVEL OF EVIDENCE

Level IV.

Adipose Tissue-Derived Products May Present Inflammatory Properties That Affect Chondrocytes and Synoviocytes from Patients with Knee Osteoarthritis

Adipose tissue-derived cell-based injectable therapies have been demonstrated to have disease-modifying effects on joint tissues in preclinical studies on animal osteoarthritis (OA) models, but clinical results are heterogeneous and not always satisfactory. The aim of this study was to investigate the influence of adipose tissue properties on the therapeutic effects of the adipose-derived product in an in vitro OA setting. Micro-fragmented adipose tissue (MF-AT) samples were obtained from 21 OA patients (mean age 51.7 ± 11.8 years, mean BMI 25.7 ± 4.1 kg/m2). The analysis of the MF-AT supernatant was performed to analyze the release of inflammatory factors. The effects of MF-AT inflammatory factors were investigated on chondrocytes and synoviocytes gene expression levels. Patients' characteristics were analyzed to explore their influence on MF-AT inflammatory molecules and on the MF-AT effects on the gene expression of chondrocytes and synoviocytes. The study results demonstrated that adipose tissue-derived products may present inflammatory properties that influence the therapeutic potential for OA treatment, with products with a higher pro-inflammatory profile stimulating a higher expression of genes related to a more inflamed and catabolic phenotype. A higher pro-inflammatory cytokine pattern and a higher pro-inflammatory effect were found in adipose tissue-derived products obtained from OA patients with higher BMI.

Joint Response to Exercise Is Affected by Knee Osteoarthritis: An Infrared Thermography Analysis

Infrared thermography can be used to evaluate the inflammation characterizing the joint environment of OA knees, but there is limited evidence on the response to physical exercise. Identifying the response to exercise of OA knees and the influencing variables could provide important information to better profile patients with different knee OA patterns. Sixty consecutive patients (38 men/22 women, 61.4 ± 9.2 years) with symptomatic knee OA were enrolled. Patients were evaluated with a standardized protocol using a thermographic camera (FLIR-T1020) positioned at 1 m with image acquisition of an anterior view at baseline, immediately after, and at 5 min after a 2-min knee flexion-extension exercise with a 2 kg anklet. Patients' demographic and clinical characteristics were documented and correlated with the thermographic changes. This study demonstrated that the temperature response to exercise in symptomatic knee OA was affected by some demographic and clinical characteristics of the assessed patients. Patients with a poor clinical knee status presented with a lower response to exercise, and women showed a greater temperature decrease than men. Not all evaluated ROIs showed the same trend, which underlines the need to specifically study the different joint subareas to identify the inflammatory component and joint response while investigating knee OA patterns.

The Minimal Clinically Important Difference Changes Greatly Based on the Different Calculation Methods

BACKGROUND

The minimal clinically important difference (MCID) for patient-reported outcome measures (PROMs) expresses both the extent of the improvement and the value that patients place on it. MCID use is becoming increasingly widespread to understand the clinical efficacy of a given treatment, define guidelines for clinical practice, and properly interpret trial results. However, there is still large heterogeneity in the different calculation methods.

PURPOSE

To calculate and compare the MCID threshold values of a PROM by applying various methods and analyzing their effect on the study results interpretation.

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 3.

METHODS

The data set used to investigate the different MCID calculation approaches was based on a database of 312 patients affected by knee osteoarthritis and treated with intra-articular platelet-rich plasma. MCID values were calculated on the International Knee Documentation Committee (IKDC) subjective score at 6 months using 2 approaches: 9 methodologies referred to an anchor-based approach and 8 methodologies to a distribution-based approach. The obtained threshold values were applied to the same series of patients to understand the effect of using different MCID methods in evaluating patient response to treatment.

RESULTS

The different methods employed led to MCID values ranging from 1.8 to 25.9 points. The anchor-based methods ranged from 6.3 to 25.9, while the distribution-based ones were from 1.8 to 13.8 points, showing a 4.1× variation of the MCID values within the anchor-based methods and a 7.6× variation within the distribution-based methods. The percentage of patients who reached the MCID for the IKDC subjective score changed based on the specific calculation method used. Among the anchor-based methods, this value varied from 24.0% to 66.0%, while among the distribution-based methods, the percentage of patients reaching the MCID varied from 44.6% to 75.9%.

CONCLUSION

This study proved that different MCID calculation methods lead to highly heterogeneous values, which significantly affect the percentage of patients achieving the MCID in a given population. The wide-ranging thresholds obtained with the different methodologies make it difficult to evaluate the real effectiveness of a given treatment questioning the usefulness of MCID, as currently available, in the clinical research.

Cell-based therapies have disease-modifying effects on osteoarthritis in animal models. A systematic review by the ESSKA Orthobiologic Initiative. Part 2: bone marrow-derived cell-based injectable therapies

PURPOSE

Aim of this systematic review was to determine if bone marrow-derived cell-based injectable therapies induce disease-modifying effects in joints affected by osteoarthritis (OA) in animal models.

METHODS

A systematic review was performed on three electronic databases (PubMed, Web of Science, Embase) according to PRISMA guidelines. A synthesis of the results was performed investigating disease-modifying effects in preclinical animal studies comparing injectable bone marrow-derived products with OA controls or other products, different formulations or injection intervals, and the combination with other products. The risk of bias was assessed according to the SYRCLE's tool.

RESULTS

Fifty-three studies were included (1819 animals) with an increasing publication trend over time. Expanded cells were used in 48 studies, point-of-care products in 3 studies, and both approaches were investigated in 2 studies. Among the 47 studies presenting results on the disease-modifying effects, 40 studies (85%) reported better results with bone marrow-derived products compared to OA controls, with positive findings evident in 14 out of 20 studies (70%) in macroscopic assessment, in 30 out of 41 studies (73%) in histological assessment, and in 10 out of 13 studies (77%) in immunohistochemical evaluations. Clinical evaluations showed positive results in 7 studies out of 9 (78%), positive imaging results in 11 studies out of 17 (65%), and positive biomarker results in 5 studies out of 10 (50%). While 36 out of 46 studies (78%) reported positive results at the cartilage level, only 3 out of 10 studies (30%) could detect positive changes at the synovial level. The risk of bias was low in 42% of items, unclear in 50%, and high in 8%.

CONCLUSION

This systematic review of preclinical studies demonstrated that intra-articular injections of bone marrow-derived products can induce disease-modifying effects in the treatment of OA, slowing down the progression of cartilage damage with benefits at macroscopic, histological, and immunohistochemical levels. Positive results have been also observed in terms of clinical and imaging findings, as well as in the modulation of inflammatory and cartilage biomarkers, while poor effects have been described on the synovial membrane. These findings are important to understand the potential of bone marrow-derived products and to guide further research to optimise their use in the clinical practice.

LEVEL OF EVIDENCE

II.

Platelet-Rich Plasma for Intra-articular Injections: Preclinical and Clinical Evidence

The use of platelet-rich plasma (PRP) has been supported by encouraging data from in vitro and preclinical in vivo studies, both in terms of safety and efficacy. This led to the wide use of PRP injections in the clinical practice, with promising results especially as a minimally invasive treatment for cartilage degeneration and osteoarthritis (OA). While many controversies remain on the best PRP formulation, the overall available clinical studies support the benefits of PRP, with functional improvement and reduction of pain-related symptoms up to 12 months, especially in young patients and early OA stages.

Cell-based therapies have disease-modifying effects on osteoarthritis in animal models. A systematic review by the ESSKA Orthobiologic Initiative. Part 1: adipose tissue-derived cell-based injectable therapies

PURPOSE

The aim of this systematic review was to determine if adipose tissue-derived cell-based injectable therapies can induce disease-modifying effects in joints affected by osteoarthritis (OA).

METHODS

A systematic review was performed on three electronic databases (PubMed, Web of Science, Embase) according to PRISMA guidelines. A synthesis of the results was performed investigating disease-modifying effects in preclinical studies comparing injectable adipose-derived products with OA controls or other products, different formulations or injection intervals, and the combination with other products. The risk of bias was assessed according to the SYRCLE's tool.

RESULTS

Seventy-one studies were included (2,086 animals) with an increasing publication trend over time. Expanded cells were used in 65 studies, 3 studies applied point of care products, and 3 studies investigated both approaches. Overall, 48 out of 51 studies (94%) reported better results with adipose-derived products compared to OA controls, with positive findings in 17 out of 20 studies (85%) in macroscopic, in 37 out of 40 studies (93%) in histological, and in 22 out of 23 studies (96%)  in immunohistochemical evaluations. Clinical and biomarker evaluations showed positive results in 14 studies out of 18 (78%) and 12 studies out of 14 (86%), while only 9 studies out of 17 (53%) of the imaging evaluations were able to detect differences versus controls. The risk of bias was low in 38% of items, unclear in 51%, and high in (11%).

CONCLUSION

The current preclinical models document consistent evidence of disease-modifying effects of adipose-derived cell-based therapies for the treatment of OA. The high heterogeneity of the published studies highlights the need for further targeted research to provide recommendations on the optimal methodologies for a more effective application of these injective therapies for the treatment of OA in clinical practice.

LEVEL OF EVIDENCE

II.

Recall Bias Affects Pain Assessment in Knee Osteoarthritis: A Pilot Study

OBJECTIVE

The objective of this study was to evaluate the recall bias of symptoms evaluation in knee osteoarthritis (OA).

DESIGN

In this multicentric pilot study, 50 patients with knee OA used a mobile App (Ecological Momentary Assessment [EMA]) to collect pain and function on two 0 to 10 numerical rating scales (NRS) 2 times a day for 2 months. At the 1-month and at the 2-month follow-up visits, patients retrospectively evaluated the mean level of pain/function of the last month. Recall bias was computed as the difference between the mean level of pain/function reported using the App and the level reported with the retrospective assessment. The correlation between the recall bias and patients' characteristics, as well as pain/function trajectories, was analyzed.

RESULTS

A statistically significant recall bias was documented with higher pain reported at 1-month with the retrospective assessment (P < 0.001). These results were confirmed also at the 2-month follow-up (P = 0.002). For function, no significant recall bias was documented. During the first and second months, 47 and 31 patients showed pain peaks, respectively. The number of pain peaks during the first month was correlated with the magnitude of the recall bias (P = 0.02).

CONCLUSIONS

The recall bias influences the retrospective self-assessment of pain at the follow-up visits and the presence of pain peaks, a common event in the patients with OA, increases the magnitude of recall bias. The EMA performed with a mobile App is a useful tool to limit the influence of recall bias in the clinical and research setting evaluation of knee OA.

Bone marrow aspirate concentrate injections provide similar results versus viscosupplementation up to 24 months of follow-up in patients with symptomatic knee osteoarthritis. A randomized controlled trial

PURPOSE

The purpose of this double-blind randomized controlled trial (RCT) was to compare clinical improvement and radiographic findings up to 2 years of follow-up of a single intra-articular injection of bone marrow aspirate concentrate (BMAC) versus hyaluronic acid (HA) for the treatment of knee osteoarthritis (OA). The hypothesis was that BMAC injection could lead to better clinical and radiographic results compared to viscosupplementation.

METHODS

Patients with bilateral knee OA were randomized to one intra-articular injection of tibial-derived BMAC in one knee and one HA injection in the contralateral knee. Sixty patients were enrolled, and 56 were studied up to the final follow-up (35 men, 21 women, mean age 57.8 ± 8.9 years), for a total of 112 knees. Patients were evaluated before the injection and at 1, 3, 6, 12, and 24 months with the IKDC subjective score, VAS for pain, and the KOOS score. Minimal clinically important difference (MCID), patient treatment judgement, and adverse events were documented, as well as bilateral X-Rays (Rosenberg view) before and after treatment.

RESULTS

No severe adverse events nor differences were reported in terms of mild adverse events (7.1% vs 5.4%, p = ns) and treatment failures (10.7% vs 12.5%, p = ns) in BMAC and HA groups, respectively. The IKDC subjective score improved from baseline to all follow-ups for BMAC (p < 0.0005), while it improved up to 12 months (p < 0.0005) and then decreased at 24 months (p = 0.030) for HA. Compared to HA, BMAC showed a higher improvement for VAS pain at 12 (2.2 ± 2.6 vs 1.7 ± 2.5, p = 0.041) and 24 months (2.2 ± 2.6 vs 1.4 ± 2.8, p = 0.002). The analysis based on OA severity confirmed this difference only in Kellgren-Lawrence 1-2 knees, while comparable results were observed in moderate/severe OA. Radiographic evaluation did not show knee OA deterioration for both treatment groups, without intergroup differences.

CONCLUSION

BMAC did not demonstrate a clinically significant superiority at short-term compared to viscosupplementation, reporting overall comparable results in terms of clinical scores, failures, adverse events, radiographic evaluation, MCID achievement, and patient treatment judgment. However, while HA results decreased over time, BMAC presented more durable results in mild OA knees.

LEVEL OF EVIDENCE

Level I.

Orthobiologic Injections for the Treatment of Hip Osteoarthritis: A Systematic Review

The use of orthobiologics is gaining increasing interest as a minimally invasive treatment for hip osteoarthritis (OA). The aim of this study was to investigate the evidence about the safety and efficacy of these products. A systematic review of the literature was performed according to the PRISMA and Cochrane guidelines. The study quality was assessed using the RoB 2.0 for randomized controlled trials (RCTs) and the modified Coleman Methodology Score (mCMS) for all studies. A total of 20 clinical studies (735 patients) was identified, 12 on PRP injections and eight on cell-based therapies (five from bone marrow, two from adipose tissue, and one from amniotic fluid). The publication trend increased over time, with over 50% of articles published from 2019. The literature analysis showed only six RCTs, all on PRP injections. The mCMS showed an overall fair methodology (mean score 59.4). While the number of studies and their methodology are still limited, the available evidence suggests safety and overall promising results, with the treatment success being inversely proportional to the severity of OA. Further high-level controlled trials are needed before drawing more definitive conclusions on the real potential of orthobiologics for the injective treatment of patients affected by hip OA.

Combined subchondral and intra-articular injections of bone marrow aspirate concentrate provide stable results up to 24 months

PURPOSE

The aim of this study was to evaluate the clinical and imaging findings up to 24 months of follow-up in patients treated with combined subchondral and intra-articular bone marrow aspirate concentrate (BMAC) injections for the treatment of knee osteoarthritis (OA).

METHODS

Thirty consecutive patients (19 males, 11 females) aged between 40 and 75 years (mean age 56.4 ± 8.1 years) with unilateral symptomatic knee OA (Kellgren-Lawrence 2-3) were included in the study. Patients were treated with combined intra-articular and subchondral bone BMAC injections (total 9 ml) under fluoroscopic control. IKDC subjective score, VAS for pain, KOOS, and EQ-VAS were prospectively evaluated up to 24 months. Radiographs were performed at baseline and at 24 months after the procedure. MRI was evaluated with the WORMS score at baseline, 6-12 months, and 24 months of follow-up. The statistical analysis was performed using SPSS v.19.0 and for all tests p < 0.05 was considered significant.

RESULTS

No major complications and a 13% failure rate were reported. The IKDC subjective score remained stable from 62.6 ± 19.4 at 12 months to 63.4 ± 17.1 at 24 months (both p < 0.0005 compared to baseline, 40.5 ± 12.5). Similar improvements were reported for all KOOS subscales, while EQ-VAS did not report any significant improvement. VAS pain worsened from 3.0 ± 1.9 at 12 months to 4.4 ± 1.8 at the final follow-up (p = 0.0001), although remaining lower compared to the baseline value of 6.3 ± 1.8 (p = 0.002). The radiographic evaluation did not reveal signs of improvement or deterioration of the OA grade. The MRI findings showed a worsening in marginal osteophytes and synovitis, but a significant reduction of bone marrow edema at 24 months (p < 0.0005).

CONCLUSION

Combined intra-articular and subchondral BMAC injections provided clinical and imaging benefits up to 24 months for the treatment of symptomatic knee OA, with durable clinical results, a low failure rate, and a significant reduction of bone marrow edema.

Prospective double-blind randomised controlled trial protocol comparing bone marrow aspirate concentrate intra-articular injection combined with subchondral injection versus intra-articular injection alone for the treatment of symptomatic knee osteoarthritis

INTRODUCTION

Subchondral and intra-articular injections of bone marrow aspirate concentrate (BMAC) showed promising results for knee osteoarthritis (OA) patients. To date, there is no evidence to demonstrate whether the combination of these treatments provides higher benefits than the intra-articular injection alone.

METHODS AND ANALYSIS

Eighty-six patients with symptomatic knee OA (aged between 40 and 70 years) are randomised to BMAC intra-articular injection combined with subchondral BMAC injection or BMAC intra-articular injection alone in a ratio of 1:1. The primary outcome is the total Western Ontario and McMaster Universities Osteoarthritis Index, the secondary outcomes are the International Knee Documentation Committee Subjective and Objective Knee Evaluation Form, the Tegner activity scale, the EuroQol-Visual Analogue Scale, and the health questionnaire European Quality of Life Five Dimension score. Additional CT and MRI evaluations are performed at the baseline assessment and at the final 12-month follow-up. The hypothesis is that the combined injections provide higher knee pain and function improvement compared with BMAC intra-articular injection alone. The primary analysis follows an intention to treat principle.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Emilia Wide Area Ethical Committee of the Emilia-Romagna Region (CE-AVEC), Bologna, Italy. Written informed consent is obtained from all the participants. Findings of this study will be disseminated through peer-reviewed publications and conference presentations.

PROTOCOL VERSION

Version 1 (14 May 2018).

TRIAL REGISTRATION NUMBER

NCT03876795.

Microfragmented Adipose Tissue Versus Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis: A Prospective Randomized Controlled Trial at 2-Year Follow-up

BACKGROUND

Intra-articular microfragmented adipose tissue (MF-AT) injections have been proposed for the treatment of knee osteoarthritis (OA).

PURPOSE

To compare a single injection of MF-AT or platelet-rich plasma (PRP) in terms of clinical outcomes and OA progression.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 118 patients with symptomatic knee OA were randomized to receive a single intra-articular injection of MF-AT or PRP. Patients were evaluated before the injection and at 1, 3, 6, 12, and 24 months with the International Knee Documentation Committee (IKDC) subjective score, Knee injury and Osteoarthritis Outcome Score (KOOS) subscales, EuroQol visual analogue scale (EQ-VAS), EuroQol 5 dimensions (EQ-5D), and visual analogue scale (VAS) for pain. Primary outcomes were the IKDC subjective score and the KOOS pain subscore at 6 months. Knees were evaluated at baseline and at 6, 12, and 24 months with radiography and high-resolution magnetic resonance imaging (MRI) using the Whole-Organ Magnetic Resonance Imaging Score (WORMS).

RESULTS

Both MF-AT and PRP provided a statistically and clinically significant improvement up to 24 months. The improvement in the IKDC subjective score from baseline to 6 months was similar in both MF-AT (41.1 ± 16.3 to 57.3 ± 18.8) and PRP (44.8 ± 17.3 to 58.4 ± 18.1) groups (P < .0005). The improvement in the KOOS pain subscore from baseline to 6 months was similar in both the MF-AT (58.4 ± 15.9 to 75.8 ± 17.4) and PRP (63.5 ± 17.8 to 75.5 ± 16.1) groups (P < .0005). Overall, no differences were found between the MF-AT and PRP groups in terms of clinical outcomes, adverse events (18.9% and 10.9%, respectively), and failures (15.1% and 25.5%, respectively). Radiographic and MRI findings did not show changes after the injection. As a secondary outcome, more patients in the MF-AT group with moderate/severe OA reached the minimal clinically important difference for the IKDC score at 6 months compared with the PRP group (75.0% vs 34.6%, respectively; P = .005).

CONCLUSION

A single intra-articular injection of MF-AT was not superior to PRP, with comparable low numbers of failures and adverse events and without disease progression. No differences were found in clinical and imaging results between the 2 biological approaches.

Meniscus treatment: biological augmentation strategies: a narrative review

Objective

An up-to-date description on the biological augmentation strategies for meniscal repair procedures was performed to highlight the main preclinical and clinical evidence available in the literature.

Background

Meniscal repair is a key surgical procedure to preserve as much meniscal tissue as possible to limit the development of knee osteoarthritis (OA). Unfortunately, the results of meniscal repair procedures are not always satisfactory, reporting an overall risk of failure of 25%, likely conditioned due to the poor vascularization of the meniscal tissue. For this reason, several biologic augmentation techniques have been developed to improve the meniscal healing process, ranging from mechanical stimulations to biological products.

Methods

A literature review was conducted on the main biological augmentation procedures combined to the meniscal repair process. A description of the rationale, surgical technique, and preclinical and clinical evidence was performed.

Conclusions

Mechanical stimulations and fibrin clot were the first techniques applied showing several limitations and not exciting results. Recently, platelet-rich plasma (PRP) augmentation to meniscal repair is slowly spreading in the clinical practice. Early evidence from comparative studies showed a significantly lower failure rate in patients treated with PRP augmentation compared with controls. Conversely, the current few and low-level data on mesenchymal stem/stromal cells (MSCs) for meniscal augmentation repair make this a promising but anecdotal topic. Further high-quality clinical studies are needed to support and guide the use of biological strategies for the augmentation of meniscus repair, PRP.

The 50 most-cited clinical articles in cartilage surgery research: a bibliometric analysis

PURPOSE

Articular cartilage lesions remain a challenge for orthopedic surgeons. The identification of the most important articles can help identifying the most influential techniques of the past, the current prevalent focus, and emerging strategies. The aim of this study was to identify milestones and trends in cartilage research.

METHODS

This study is a bibliometric analysis based on published articles. All citation count data included in the "Scopus database" were used to identify eligible studies up to December 2020. The 50 most-cited articles on cartilage surgery were ranked based on the citation count and analyzed regarding citation density and quality (Coleman score and RoB 2.0 tool). A further search was performed to identify the most promising clinical studies among the latest publications on cartilage surgery.

RESULTS

Different kinds of cartilage treatments were investigated in the 50 most-cited clinical articles. Regenerative techniques with chondrocytes were the most reported with a total of 23 articles, followed by microfracture technique in 17 articles and mosaicplasty or osteochondral autograft transplantation (OAT) in 11. Forty-five articles focused on the knee. A higher citation density was found in the most recent articles (p = 0.004). The study of the most promising landmarks of the most recent articles showed new cell-free or tissue engineering-based procedures and an overall increasing quality of the published studies.

CONCLUSION

This bibliometric analysis documented an increasing interest in cartilage surgery, with efforts toward high-quality studies. Over the years, the focus switched from reconstructive toward regenerative techniques, with emerging options including cell-free and tissue-engineering strategies to restore the cartilage surface.

LEVEL OF EVIDENCE

IV.

Leukocyte-Rich versus Leukocyte-Poor Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis: A Double-Blind Randomized Trial

BACKGROUND

Platelet-rich plasma (PRP) is gaining large interest in clinical practice as a minimally invasive injective treatment for knee osteoarthritis (OA). Different preparation methods are available, and the presence of leukocytes, deemed detrimental in some preclinical studies, is one of the most debated aspects regarding PRP efficacy.

PURPOSE

To compare the safety and effectiveness of leukocyte-rich PRP (LR-PRP) and leukocyte-poor PRP (LP-PRP) for the treatment of knee OA.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 192 patients with symptomatic knee OA (Kellgren-Lawrence grade 1-3) were randomly allocated to 3 weekly injections of LR-PRP or LP-PRP. LP-PRP was obtained with a filter for leukodepletion. LR-PRP and LP-PRP were divided into aliquots of 5 mL, with a mean platelet concentration of 1146.8 × 10⁹/L and 1074.9 × 10⁹/L and a mean leukocyte concentration of 7991.4 × 10⁶/L and 0.1 × 10⁶/L, respectively. Patients were evaluated at baseline and thereafter at 2, 6, and 12 months for the primary outcome, the International Knee Documentation Committee (IKDC) subjective score; and for secondary outcomes, the Knee injury and Osteoarthritis Outcome Score (KOOS) subscales, EuroQol-visual analog scale (EQ-VAS), and Tegner score.

RESULTS

No differences between groups were observed in terms of absolute values or improvement of the clinical scores across all follow-up intervals. The mean IKDC subjective score at baseline and 12 months improved from 45.6 to 60.7 in the LR-PRP group as compared with 46.8 to 62.9 in the LP-PRP group (P = .626). No severe adverse events were described in either group, although 15 mild adverse events (knee pain or swelling) were reported: 12.2% for LR-PRP and 4.7% for LP-PRP (P = .101). No statistically significant difference was also found between LR-PRP and LP-PRP in terms of failures (7.8% vs 3.5%, P = .331).

CONCLUSION

This double-blind randomized trial showed that 3 intra-articular LR-PRP or LP-PRP injections produced similar clinical improvement in the 12 months of follow-up in patients with symptomatic knee OA. Both treatment groups reported a low number of adverse events, without intergroup differences. The presence of leukocytes did not significantly affect the clinical results of PRP injections.

REGISTRATION

NCT02923700 (ClinicalTrials.gov identifier).

Synovial Fluid Biomarkers in Knee Osteoarthritis: A Systematic Review and Quantitative Evaluation Using BIPEDs Criteria

OBJECTIVE

The aim of this systematic review was to analyze the evidence about the efficacy of the several synovial fluid (SF) biomarkers proposed for knee osteoarthritis (OA), categorizing them by both molecular characteristics and clinical use according to the BIPEDs criteria, to provide a comprehensive and structured overview of the current literature.

DESIGN

A systematic review was performed in May 2020 on PubMed, Cochrane Library, and Embase databases about SF biomarkers in patients with knee OA. The search was limited to articles in the last 20 years on human studies, involving patients with knee OA, reporting SF biomarkers. The evidence for each selected SF biomarker was quantified according to the 6 categories of BIPEDs classification.

RESULTS

A total of 159 articles were included in the qualitative data synthesis and 201 different SF biomarkers were identified. Among these, several were investigated multiple times in different articles, for a total of 373 analyses. The studies included 13,557 patients with knee OA. The most promising SF biomarkers were C4S, IL-6, IL-8, Leptin, MMP-1/3, TIMP-1, TNF-α, and VEGF. The "burden of disease" and "diagnostic" categories were the most represented with 132 and 106 different biomarkers, respectively.

CONCLUSIONS

The systematic review identified numerous SF biomarkers. However, despite the high number of studies on the plethora of identified molecules, the evidence about the efficacy of each biomarker is supported by limited and often conflicting findings. Further research efforts are needed to improve the understanding of SF biomarkers for a better management of patients with knee OA.

Subchondral and intra-articular injections of bone marrow concentrate are a safe and effective treatment for knee osteoarthritis: a prospective, multi-center pilot study

PURPOSE

Subchondral bone is becoming a treatment target for knee OA patients, with promising early findings on the use of bone marrow aspirate concentrate (BMAC). The aim of this prospective, multi-centric pilot study was to evaluate safety as well as clinical and MRI outcomes of a combined approach of intra-articular and subchondral BMAC injections.

METHODS

Thirty patients (19 men, 11 women, 56.4 ± 8.1 years) with symptomatic knee OA were treated with a combination of an intra-articular and two subchondral BMAC injections (femoral condyle and tibial plateau). Patients were evaluated at baseline and at 1-3-6-12 months of follow-up with the IKDC subjective, VAS, KOOS, and EQ-VAS scores. The MRI evaluation was performed with the WORMS score.

RESULTS

No major complications were reported and only two patients were considered treatment failures, requiring a new injective or surgical treatment. The IKDC subjective score improved significantly from 40.5 ± 12.5 to 59.9 ± 16.1 at 3 months, 59.1 ± 12.2 at 6 months, and 62.6 ± 19.4 at 12 months (p < 0.0005). A similar improvement was reported for VAS pain and all KOOS subscales at all follow-ups, while EQ-VAS did not show any significant improvement. The MRI analysis showed a significant bone marrow edema reduction (p = 0.003), while the remaining WORMS parameters did not show any significant changes.

CONCLUSION

The pilot evaluation of this combined BMAC injective treatment showed safety and positive outcome up to 12 months of follow-up in patients with symptomatic knee OA associated with subchondral bone alterations. These findings suggest that targeting both subchondral bone and joint environment can provide promising results, and that BMAC can be a valid option for this combined approach to treat knee OA.

Minimal Clinically Important Difference and Patient Acceptable Symptom State in Patients With Knee Osteoarthritis Treated With PRP Injection

Background:

Although several injection-based treatments have been proposed to address knee osteoarthritis (OA), it is often difficult to understand the clinical relevance of the obtained results. The psychometric measures of minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) were developed to better interpret study findings.

Purpose:

To establish the MCID and the PASS for the International Knee Documentation Committee (IKDC) Subjective score and the Knee injury and Osteoarthritis Outcome Score (KOOS) in patients treated with intra-articular platelet-rich plasma (PRP) injections for knee OA.

Study Design:

Case series; Level of evidence, 4.

Methods:

This study included 215 patients with knee OA (68% men, 32% women; age, 53.2 ± 11.3 years; body mass index, 26.8 ± 4.3 kg/m²) who underwent intra-articular PRP injections. Patients were assessed through the IKDC Subjective score and KOOS subscales, and the MCID and the PASS for both measures were independently calculated at 6 and 12 months post-injection. The MCID was calculated using the value equal to half of the standard deviation of the overall cohort improvement. The PASS was assessed using a 2-point scale (satisfied or not satisfied), with threshold values being detected through a receiver operating characteristic curve analysis and the Youden index to maximize the sensitivity and the specificity of the threshold values.

Results:

All scores improved significantly from baseline to 6 months and baseline to 12 months (P < .001 for all scores). All scores were stable from 6 to 12 months except for the KOOS Quality of Life subscale, which improved further (P = .033). For the IKDC, the MCID values were 8.6 and 8.5 points and the PASS scores were 59.7 and 62.1 at 6 and 12 months, respectively. Overall, the MCID and the PASS for all KOOS subscales remained constant at the 2 follow-up points. The percentage of patients who achieved the MCID and the PASS was higher than 85% at both 6 and 12 months post-injection.

Conclusion:

This study provided the MCID and PASS thresholds for the IKDC and KOOS scores in patients with knee OA treated with PRP injections. These psychometric measures may allow a better interpretation of the clinical relevance of injection-based treatment outcomes for knee OA.

Multi-layer cell-free scaffolds for osteochondral defects of the knee: a systematic review and meta-analysis of clinical evidence

Purpose

The aim of this study was to analyze the clinical results provided by multi-layer cell-free scaffolds for the treatment of knee osteochondral defects.

Methods

A systematic review was performed on PubMed, Web of Science, and Cochrane to identify studies evaluating the clinical efficacy of cell-free osteochondral scaffolds for knee lesions. A meta-analysis was performed on articles reporting results of the International Knee Documentation Committee (IKDC) and Tegner scores. The scores were analyzed as improvement from baseline to 1, 2, and ≥ 3 years of follow-up. The modified Coleman Methodology Score was used to assess the study methodology.

Results

A total of 34 studies (1022 patients) with a mean follow-up of 35 months was included. Only three osteochondral scaffolds have been investigated in clinical trials: while TruFit® has been withdrawn from the market for the questionable results, the analysis of MaioRegen and Agili-C™ provided clinical improvements at 1, 2, and ≥ 3 years of follow-up (all significantly higher than the baseline, p < 0.05), although with a limited recovery of the sport-activity level. A low rate of adverse events and an overall failure rate of 7.0% were observed, but the overall evidence level of the available studies is limited.

Conclusions

Multi-layer scaffolds may provide clinical benefits for the treatment of knee osteochondral lesions at short- and mid-term follow-up and with a low number of failures, although the sport-activity level obtained seems to be limited. Further research with high-level studies is needed to confirm the role of multi-layer scaffold for the treatment of knee osteochondral lesions.

Cell-Free Scaffolds in Cartilage Knee Surgery: A Systematic Review and Meta-Analysis of Clinical Evidence

OBJECTIVE

To evaluate current evidence and results of cell-free scaffold techniques for knee chondral lesions.

DESIGN

A systematic review was conducted on 3 medical electronic databases according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines, and the methodological quality was assessed with a modified Coleman Methodology Score. A meta-analysis was performed on the articles reporting results for visual analogue scale (VAS), Lysholm, and International Knee Documentation Committee (IKDC) scores. In order to investigate the clinical results improvement over time of cell-free cartilage scaffold implantation, all scores were reported and analyzed as improvement from basal scores at 1, 2, and ≥3 years' follow-up.

RESULTS

A total of 23 studies involving 521 patients were included in the qualitative data synthesis. The Coleman score showed an overall poor study quality with the majority of studies reporting results at short-/mid-term follow-up. Sixteen studies were included in the meta-analysis, showing a significant improvement from basal score at 1, 2, and ≥3 years' follow-up. The improvement reached at 1 year remained stable up to the last follow-up for all scores.

CONCLUSIONS

The current literature suggests that cell-free scaffolds may provide good clinical short-/mid-term results; however, the low evidence of the published studies and their short mean follow-up demand further evidence before more definitive conclusions can be drawn on their real potential over time and on their advantages and disadvantages compared to the cell-based strategies for the treatment of cartilage lesions.

Matrix-assisted chondrocyte transplantation with bone grafting for knee osteochondritis dissecans: stable results at 12 years

PURPOSE

To document clinical and radiological results of arthroscopic matrix-assisted autologous chondrocyte transplantation (MACT) combined with bone grafting for the treatment of knee osteochondritis dissecans (OCD) at long-term follow-up.

METHODS

Thirty-one knees in 29 patients (20.4 ± 5.7 years) were treated for symptomatic unfixable OCD lesions (2.6 ± 1.1 cm²) and prospectively evaluated at 2, 5, and 12 years (average, minimum 10 years). Patients were evaluated over time with IKDC subjective score, EQ-VAS, and Tegner scores. Failures were also documented. At the final follow-up, MRI evaluation was performed in 14 knees with the MOCART 2.0 score.

RESULTS

Beside 4 early failures, an overall clinical improvement was documented: the IKDC subjective score improved from 39.9 ± 16.8 to 82.1 ± 17.0 and 84.8 ± 17.2 at 2 and 5 years, respectively (p < 0.0005), and remained stable for up to 12 years (85.0 ± 20.2). EQ-VAS and Tegner scores presented similar trends, but patients did not reach their original activity level. Worse results were obtained for lesions bigger than 4 cm². At MRI evaluation, subchondral bone abnormalities were detected in over 85% of knees at long-term follow-up.

CONCLUSIONS

Arthroscopic bone grafting followed by MACT for unfixable knee OCD can offer a promising and stable clinical outcome over time in lesions smaller than 4 cm², with a low failure rate of 13%. Persistent subchondral alterations were documented at long-term MRI evaluation, suggesting the limits of this approach to regenerate the osteochondral unit in patients affected by knee OCD.

LEVEL OF EVIDENCE

IV.

Platelet-Rich Plasma Augmentation to Microfracture Provides a Limited Benefit for the Treatment of Cartilage Lesions: A Meta-analysis

Background:

Microfracture is the most common first-line option for the treatment of small chondral lesions, although increasing evidence shows that the clinical benefit of microfracture decreases over time. Platelet-rich plasma (PRP) has been suggested as an effective biological augmentation to improve clinical outcomes after microfracture.

Purpose:

To evaluate the clinical evidence regarding the application of PRP, documenting safety and efficacy of this augmentation technique to improve microfracture for the treatment of cartilage lesions.

Study Design:

Systematic review; Level of evidence, 3.

Methods:

A systematic review was performed in PubMed, EBSCOhost database, and the Cochrane Library to identify comparative studies evaluating the clinical efficacy of PRP augmentation to microfracture. A meta-analysis was performed on articles that reported results for visual analog scale (VAS) for pain, International Knee Documentation Committee (IKDC), and American Orthopaedic Foot and Ankle Society (AOFAS) scores. Risk of bias was documented through use of the Cochrane Collaboration Risk of Bias 2.0 and Risk of Bias in Non-randomized Studies of Interventions assessment tools. The quality assessment was performed according to the Grading of Recommendations Assessment, Development and Evaluation guidelines.

Results:

A total of 7 studies met the inclusion criteria and were included in the meta-analysis: 4 randomized controlled trials, 2 prospective comparative studies, and 1 retrospective comparative study, for a total of 234 patients. Of the 7 studies included, 4 studies evaluated the effects of PRP treatment in the knee, and 3 studies evaluated effects in the ankle. The analysis of all scores showed a difference favoring PRP treatment in knees (VAS, P = .002 and P < .001 at 12 and 24 months, respectively; IKDC, P < .001 at both follow-up points) and ankles (both VAS and AOFAS, P < .001 at 12 months). The improvement offered by PRP did not reach the minimal clinically important difference (MCID).

Conclusion:

PRP provided an improvement to microfracture in knees and ankles at short-term follow-up. However, this improvement did not reach the MCID, and thus it was not clinically perceivable by the patients. Moreover, the overall low evidence and the paucity of high-level studies indicate further research is needed to confirm the potential of PRP augmentation to microfracture for the treatment of cartilage lesions.