Good short- to medium-term results after osteochondral autograft transplantation (OAT) in middle-aged patients with focal, non-traumatic osteochondral lesions of the knee

Anterior Distal Femoral Hemiepiphysiodesis Procedure: A Comparison of Antegrade Versus Retrograde Insertion

BACKGROUND

Anterior distal femoral hemiepiphysiodesis (ADFH) is an effective surgery to correct knee flexion contractures. ADFH entails inserting 2 screws through the anterior third of the distal femoral physis, typically inserted in an antegrade fashion (proximal to distal across the physis). However, the screws must traverse significant soft tissue structures, thereby impeding simple insertion parallel to the mechanical axis of the femur. Our surgeons have developed a novel technique using a retrograde approach with a shorter path through soft tissue and an entry point with a broad surface for screw insertion. It is unknown how retrograde ADFH impacts surgical time, clinical outcomes, and complication rates. The purpose was to compare retrograde to antegrade ADFH on surgical times, maximum knee extension angles, and complications.

METHODS

Twenty-eight patients (53 knees) who underwent ADFH [12 antegrade (23 knees); 16 retrograde (30 knees)] were retrospectively reviewed. Surgical approach, time, pre and 2-year post-ADFH knee extension angles, and complications were retrieved. The effect of the approach on surgical time was analyzed through an independent t test. The differences between surgical approach on pre-ADFH and post-ADFH knee extension angles were analyzed using a mixed factor RMANOVA. χ2 performed on complication frequencies. Alpha set to P≤0.05.

RESULTS

No statistically significant difference was found between surgical insertion and removal times for antegrade ADFH (insertion: 85.2±30.2 min; removal: 118.0±106.0 min) compared with the retrograde ADFH (insertion: 61.7±29.4 min; removal: 56.2±22.8 min). A main effect of time was observed for knee extension angles (P<0.001). Both groups improved knee extension at 2-year post ADFH (antegrade 5.9±7.3 degrees; retrograde 8.6±8.7 degrees). No differences were found between antegrade and retrograde ADFH on knee extension (P>0.05). One complication was observed in each approach (retrograde: 1/16 patients, 2/30 knees; antegrade: 1/12 patients, 1/23 knees).

CONCLUSIONS

Retrograde had comparable clinical effectiveness and complication rate as antegrade. An advantage of retrograde is the ease of hardware insertion and removal. Combined, these findings suggest retrograde insertion as a viable alternative approach to ADFH.

LEVEL OF EVIDENCE

Level III.

Autologous bone grafting in combination with autologous chondrocyte implantation yields favourable outcomes in the treatment of osteochondral defects of the knee: A systematic literature review

PURPOSE

This study addresses the gap in the current literature by evaluating the combined treatment of autologous bone grafting and autologous chondrocyte implantation (ABCI) for osteochondral defects of the knee. It aims to evaluate clinical outcomes against methodological quality and to summarize histological results and surgical techniques.

METHODS

A thorough search was conducted across Pubmed, Cochrane and Embase databases. Studies reporting clinical outcomes of ABCI for osteochondral defects of the knee were included. Patient-reported outcome measures (PROMs), failure rates, methodological quality and potential conflicts of interest were evaluated. Histological results and surgical techniques were summarized.

RESULTS

Eighteen studies with 344 analyzed patients met the eligibility criteria for inclusion. All studies showed a significant improvement (p < 0.05) across different PROMs (subjective International Knee Documentation Committee score, Cincinnati Knee Rating System, Visual Analogue Scale, Lysholm Score, Tegner Activity Scale, Knee injury and Osteoarthritis Outcome Score and Knee Society Score) compared to the preoperative status. Failure rates ranged from 0% to 17.6%, with a mean follow-up of 73.2 months (range: 9.0-143.6 months). Methodological quality was low to medium, including only one comparative study. Six studies reviewed reported a potential conflict of interest. The histological assessment showed effective bonding between autologous chondrocytes and bone graft. A large degree of variability was observed in the operative technique used.

CONCLUSION

The current literature suggests that ABCI yields good clinical outcomes at mid- to long-term follow-up with favourable histological results for osteochondral defects of the knee. However, future research should focus on high-quality comparative studies to better guide treatment choices. Introducing ABCI as the standard abbreviation may enhance clarity in future research.

LEVEL OF EVIDENCE

Level IV.

Retrograde Insertion Approach for Anterior Distal Femoral Hemiepiphysiodesis Procedure: A Case Report

CASE

A 13-year-old adolescent boy with spastic diplegic cerebral palsy (CP) presented with crouch gait and bilateral knee flexion contractures (KFCs). After failure of conservative treatments, the patient was referred to orthopaedics for surgical intervention. Anterior distal femoral hemiepiphysiodesis (ADFH), using a retrograde approach, and Strayer gastrocnemius recession were performed bilaterally. No complications were reported during surgery/follow-up. Full-active knee extension and improved gait were achieved.

CONCLUSION

KFC is prevalent in ambulatory patients with CP, reducing gait function. Retrograde ADFH is an effective surgical intervention to reduce KFC and improve gait, and offers simpler insertion/removal than the traditional antegrade technique.

Factors Affecting Choice of Surgical Treatment of Cartilage Lesions of the Knee: An Analysis of Data From 5143 Patients From the German Cartilage Registry (KnorpelRegister DGOU)

Background

Symptomatic full-thickness cartilage lesions of the knee joint are considered an indication for cartilage repair surgery. Patient- and lesion-specific factors like age, nutritional status, etiology of defect, or integrity of corresponding joint surface remain controversial in indicating cartilage repair surgery. Furthermore, the selection of the most suitable cartilage repair technique for a specific cartilage lesion remains debatable.

Purpose

To evaluate indications and choice of treatment method for cartilage repair surgery, depending on patient- and lesion-specific data from the German Cartilage Registry.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

A total of 6305 consecutive patients who underwent cartilage repair surgery of the knee evaluated and 5143 complete datasets were included in the analysis (follow-up rate, 81.5%). Patient-specific (age, body mass index, smoking status, previous operations, clinical leg axis) and lesion-specific (size, grading, location, etiology) data were provided by the attending surgeon at the time of surgery. Appropriate statistical tests were used to compare data depending on type and normality of data. Multivariable logistic regressions were calculated to investigate independent factors for the choice of specific cartilage repair techniques.

Results

The median size of treated cartilage lesions was 3.6 cm2, and most defects were of degenerative origin (54.8%). Of the registered patients, 39.2% were categorized as overweight and 19.6% as obese, while 23.3% were smokers. The most prevalently documented operative techniques were the autologous chondrocyte implantation (ACI) (52.4%), bone marrow stimulation (BMS) (17.3%), and BMS augmented with collagen scaffolds (9.3%). Independent factors that made the use of ACI more likely were bigger lesion size, previous surgery at the joint, and lesions located at the trochlea or the patella. On the contrary, BMS or augmented BMS were preferred in older patients, with damaged corresponding joint surface, and with more concomitant surgeries.

Conclusion

Cartilage repair surgery was indicated irrespective of nutritional status, smoking status, or etiology of the treated lesion. ACI was the most prevalent technique and was preferred for younger patients and patellar lesions. While older patients with degenerative changes to the joint were not excluded from cartilage repair surgery, the use of ACI was restricted.

A Review of the Role of Bioreactors for iPSCs-Based Tissue-Engineered Articular Cartilage

BACKGROUND

Osteoarthritis (OA) is the most common degenerative joint disease without an ultimate treatment. In a search for novel approaches, tissue engineering (TE) has shown great potential to be an effective way for hyaline cartilage regeneration and repair in advanced stages of OA. Recently, induced pluripotent stem cells (iPSCs) have been appointed to be essential stem cells for degenerative disease treatment because they allow a personalized medicine approach. For clinical translation, bioreactors in combination with iPSCs-engineerd cartilage could match patients needs, serve as platform for large-scale patient specific cartilage production, and be a tool for patient OA modelling and drug screening. Furthermore, to minimize in vivo experiments and improve cell differentiation and cartilage extracellular matrix (ECM) deposition, TE combines existing approaches with bioreactors.

METHODS

This review summarizes the current understanding of bioreactors and the necessary parameters when they are intended for cartilage TE, focusing on the potential use of iPSCs.

RESULTS

Bioreactors intended for cartilage TE must resemble the joint cavity niche. However, recreating human synovial joints is not trivial because the interactions between various stimuli are not entirely understood.

CONCLUSION

The use of mechanical and electrical stimulation to differentiate iPSCs, and maintain and test chondrocytes are key stimuli influencing hyaline cartilage homeostasis. Incorporating these stimuli to bioreactors can positively impact cartilage TE approaches and their possibility for posterior translation into the clinics.

Autologous osteochondral transplantation for focal femoral condyle defects: Comparison of mosaicplasty by arthrotomy vs. arthroscopy

BACKGROUND

While many studies have reported the outcomes of open mosaicplasty, data on arthroscopic mosaicplasty are scarce. Only two cadaver studies have compared arthrotomy and arthroscopy. Moreover, the patello-femoral joint, which is the main donor site, has never been assessed using a specific functional score. The objective of this in vivo study was to compare arthrotomy and arthroscopy for mosaicplasty using both a global functional knee score and a specific score of the patello-femoral joint.

HYPOTHESIS

The arthroscopic technique results in better functional patello-femoral outcomes.

MATERIAL AND METHODS

We retrospectively compared two groups of 17 patients who underwent mosaicplasty for focal condylar cartilage defects, at our department between 2009 and 2019. Functional outcomes were assessed using the Kujala score and the Lysholm score, at least 1 year after surgery. The return to sports was assessed using the Tegner score.

RESULTS

Mean follow-up was 67.4±15.9 months in the arthrotomy group and 45.2±35.1 months in the arthroscopy group (p<0.01). Cartilage defect size was similar in the two groups (arthrotomy: 1.21±0.91cm²; arthroscopy: 0.92±1.23cm²; p=0.052). The mean Kujala score was 85±21.3 in the arthrotomy group and 91.9±13.7 in the arthroscopy group (p=0.064). The mean Lysholm score was 83.9±19.8 with arthrotomy and 89.5±14.9 with arthroscopy (p=0.1). The Kujala score was greater than 95 in 4 (26%) arthrotomy patients and 13 (81%) arthroscopy patients (p=0.003). The Lysholm score was higher than 95 in 4 (26%) arthrotomy patients and 12 (75%) arthroscopy patients (p=0.012). No patient underwent surgical revision for autograft failure.

DISCUSSION

This is the first clinical study comparing arthrotomy and arthroscopy for mosaicplasty. Clinical outcomes were good with both techniques. The proportion of patients with excellent Lysholm and Kujala functional scores was significantly higher in the arthroscopy group than in the arthrotomy group. This result may be ascribable to decreased donor-site morbidity obtained with arthroscopy.

LEVEL OF EVIDENCE

IV, retrospective observational comparative study.

Arthroscopic Osteochondral Autograft Transfer System Procedure of the Lateral Femoral Condyle with Donor-Site Backfill Using Osteochondral Allograft Plug

The osteochondral autograft transfer system (OATS) procedure is at the forefront of cartilage restoration surgeries of the knee, offering superior return to sport rates and long-term functionality. This technique reports an arthroscopic OATS procedure of the lateral femoral condyle with donor-site backfill using an osteochondral allograft plug. Potential complications from unfilled donor site sockets are eliminated through donor site backfill with an allograft plug.

Osteochondral tissue engineering: Perspectives for clinical application and preclinical development

The treatment of osteochondral defects (OCD) remains challenging. Among currently available surgical treatments for OCDs, scaffold-based treatments are promising to regenerate the osteochondral unit. However, there is still no consensus regarding the clinical effectiveness of these scaffold-based therapies for OCDs. Previous reviews have described the gradient physiological characteristics of osteochondral tissue and gradient scaffold design for OCD, tissue engineering strategies, biomaterials, and fabrication technologies. However, the discussion on bridging the gap between the clinical need and preclinical research is still limited, on which we focus in the present review, providing an insight into what is currently lacking in tissue engineering methods that failed to yield satisfactory outcomes, and what is needed to further improve these techniques. Currently available surgical treatments for OCDs are firstly summarized, followed by a comprehensive review on experimental animal studies in recent 5 years on osteochondral tissue engineering. The review will then conclude with what is currently lacking in these animal studies and the recommendations that would help enlighten the community in developing more clinically relevant implants.

The translational potential of this article

This review is attempting to summarize the lessons from clinical and preclinical failures, providing an insight into what is currently lacking in TE methods that failed to yield satisfactory outcomes, and what is needed to further improve these implants.

Autologous Matrix-Induced Chondrogenesis (AMIC) and Microfractures for Focal Chondral Defects of the Knee: A Medium-Term Comparative Study

Introduction: The potential of autologous matrix-induced chondrogenesis (AMIC) to restore unipolar focal chondral defects of the knee is promising. However, the outcome compared to microfracturing (MFx) for certain defect sizes (2–3 cm²) is still uncertain. Therefore, the present study compared primary isolated AMIC versus MFx in a cohort of patients with borderline sized focal unipolar chondral defects of the knee at midterm follow-up. Methods: Patients with chondral defects of the knee who underwent AMIC or MFx were compared. An arthroscopic approach was used for MFx, and a minimally invasive parapatellar arthrotomy for AMIC. For those patients who underwent AMIC, a collagen membrane was used with fibrin glue. The patients answered independently: Visual Analogic Scale (VAS), Tegner Activity Scale, International Knee Documentation Committee (IKDC), and the Lysholm scores. Results: A total of 83 patients with a mean age of 30.2 and body mass index (BMI) of 26.9 kg/m² were recruited. Of them, 33.7% (28 of 83) were women, and 55.4% (46 of 83 patients) had defects in the right knee. The mean length of symptoms before surgery was 43.3 months. The mean size of the defect was 2.7 cm². The mean length of follow-up was 42.1 months. No difference was found in terms of symptoms and follow-up length, mean age and BMI, mean size of defect, sex, and side. The AMIC cohort reported greater IKCD (p > 0.0001), Lysholm (p = 0.002), VAS (p = 0.01), Tegner (p = 0.004) scores. The AMIC cohort reported lower rate of failure (p = 0.005) and revision surgery (p = 0.02). No difference was found in the rate of arthroplasty (p = 0.2). No delamination or hypertrophy were detected. Conclusion: AMIC demonstrated superiority over MFx for focal unipolar chondral defects of the knee. At approximately 40 months follow-up, the IKDC, Lysholm, and VAS scores were greater in the AMIC group. Patients treated with AMIC also demonstrated a higher level of sport activity, and lower rates of failure and revision surgeries.

Arthroscopic versus Open Osteochondral Autograft Transplantation (Mosaicplasty) for Cartilage Damage of the Knee: A Systematic Review

Osteochondral autograft transplantation (OAT) is a surgical option for repairing cartilage damage in knees, and can be performed using open or arthroscopic procedures. The aim of this review was to report clinical outcomes, postoperative complications, defect location, and defect size between open and arthroscopic OATs. Three electronic databases (EMBASE, PUBMED, and MEDLINE) were searched for relevant articles. In regard to eligibility criteria, knee articular damage cases solely treated with OAT were included and cases concomitant with ligament reconstruction, limb realignment, and meniscus repair were excluded. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and descriptive statistics are presented. A total of 24 studies were included with a total sample of 1,139 patients (532 in open OAT vs. 607 in arthroscopic OAT). Defect size in open OAT was three times larger than that of arthroscopic OAT (2.96 ± 0.76 vs. 0.97 ± 0.48 cm²). In terms of defect location, the medial femoral condyle (MFC) was the most common (75.4%), followed by the lateral femoral condyle (LFC; 12.1%), patella (6.7%), and trochlea (5.7%). All of these defect locations were treated with open OAT, whereas arthroscopic OAT treatments were restricted to the MFC and LFC. The clinical outcomes were overall favorable with the modified Hospital for Special Surgery knee scores being 89.6 ± 8.0 (36.1-month follow-up) versus 90.4 ± 6.0 (89.5-month follow-up) and the Lysholm scores being 81.6 ± 8.9 (44.2-month follow-up) and 83.3 ± 7.4 (12.0-month follow-up) between open and arthroscopic OATs, respectively. Fifty-three postoperative complications were observed (39/279 vs. 14/594) and the most common complication was hemarthrosis (13/39 in open, vs. 1/14 in arthroscopic OAT). The overall clinical outcomes were favorable in open and arthroscopic OATs, whereas open OAT allowed for treatment of lesions approximately three times greater in dimension than in arthroscopic OAT. Also, defect location was restricted to MFC and LFC in arthroscopic OAT. The most common complication was hemarthrosis.

Osteochondral Autograft Transplant as a Potential Salvage Procedure for Articular Cartilage Defects of the Lateral Compartment in Lateral Meniscus-Deficient Knees: Results From a Country With Limited Availability of Meniscal Transplant

Background:

The treatment of a meniscus-deficient knee is challenging, especially when patients are young and active and are not favorable candidates for prosthetic joint replacement.

Hypothesis:

We hypothesized that osteochondral autologous transplant (OAT) alone can be considered a salvage treatment for patients with cartilage damage of the lateral compartment of the knee, even with lateral meniscal deficiency, if the knee alignment is close to neutral.

Study Design:

Case series; Level of evidence, 4.

Methods:

Patients with lateral meniscal deficiency, whose femorotibial angle was 170° to 180° and who underwent OAT on the lateral compartment of the knee without concomitant realignment osteotomy, were retrospectively included in this study. The International Knee Documentation Committee (IKDC) subjective score and the Japanese Orthopaedic Association score for knee osteoarthritis (JOA knee score) were recorded. The International Cartilage Repair Society (ICRS) cartilage repair assessment was used to evaluate the repaired cartilage at second-look arthroscopy.

Results:

The study included 10 patients (mean ± SD age, 31.7 ± 19.7 years; 3 men and 7 women) who had ICRS grade 4 cartilage lesions (mean size, 3.5 ± 1.7 cm²); the mean follow-up was 73.8 ± 42.5 months. From preoperative assessment to final follow-up, the mean IKDC subjective score improved significantly from 53.5 ± 10.0 to 85.4 ± 10.1, and the mean JOA knee score improved significantly from 81.0 ± 8.4 to 95.6 ± 5.3 (P = .004 for both). One patient with a femorotibial angle of 170° underwent revision distal femoral osteotomy owing to prolonged symptoms and progression of the valgus deformity, and 2 other patients with femorotibial angles of 170° and 171° also exhibited progression of valgus malalignment or low clinical scores postoperatively. Patients with a favorable femorotibial angle (174°-178°) exhibited relieved symptoms and preservation of femorotibial angle alignment within 1° of change at follow-up. At second-look arthroscopy (n = 8 patients), 6 patients had an ICRS score of nearly normal or normal.

Conclusion:

In the study patients, for which a meniscal allograft was unavailable, the OAT procedure was able to relieve the symptoms associated with cartilage lesions, even with lateral meniscal deficiency, when the femorotibial angle alignment was close to neutral.

In vitro and in vivo study on the osseointegration of BCP-coated versus uncoated nondegradable thermoplastic polyurethane focal knee resurfacing implants

Focal knee resurfacing implants (FKRIs) are intended to treat cartilage defects in middle-aged patients. Most FKRIs are metal-based, which hampers follow-up of the joint using magnetic resonance imaging and potentially leads to damage of the opposing cartilage. The purpose of this study was to develop a nondegradable thermoplastic polyurethane (TPU) FKRI and investigate its osseointegration. Different surface roughness modifications and biphasic calcium phosphate (BCP) coating densities were first tested in vitro on TPU discs. The in vivo osseointegration of BCP-coated TPU implants was subsequently compared to uncoated TPU implants and the titanium bottom layer of metal control implants in a caprine model. Implants were implanted bilaterally in stifle joints and animals were followed for 12 weeks, after which the bone-to-implant contact area (BIC) was assessed. Additionally, 18F-sodium-fluoride (18F-NaF) positron emission tomography PET/CT-scans were obtained at 3 and 12 weeks to visualize the bone metabolism over time. The BIC was significantly higher for the BCP-coated TPU implants compared to the uncoated TPU implants (p = .03), and did not significantly differ from titanium (p = .68). Similar 18F-NaF tracer uptake patterns were observed between 3 and 12 weeks for the BCP-coated TPU and titanium implants, but not for the uncoated implants. TPU FKRIs with surface modifications could provide the answer to the drawbacks of metal FKRIs.

Osteochondritis Dissecans in the Knee of Skeletally Immature Patients: Rates of Persistent Pain, Osteoarthritis, and Arthroplasty at Mean 14-Years' Follow-Up

OBJECTIVE

Osteochondritis dissecans (OCD) is a knee disorder of predominately pediatric populations. Because of low incidence, it has traditionally been difficult to study OCD. The purpose of this study was to report long-term outcomes of skeletally immature OCD lesions and determine risk factors for persistent knee pain at final follow-up.

DESIGN

A geographic database of more than 500,000 patients was reviewed to identify patients with knee OCD. Clinical course including operative management, persistent knee pain, and total knee arthroplasty (TKA) were analyzed through review of radiographs, magnetic resonance images, and physician notes.

RESULTS

A total of 95 skeletally immature patients (70 male, 25 female, mean age 12.5 ± 2.0 years) were followed for a mean of 14 years (range, 2-40 years). Fifty-three patients were treated operatively and 42 were treated nonoperatively. At final follow-up, 13 patients noted persistent knee pain, 8 treated operatively versus 5 treated nonoperatively. Risk factors for knee pain were female gender, patellar lesions, and unstable lesions. Four patients (8%) treated operatively and 2 patients (5%) treated nonoperatively developed symptomatic osteoarthritis at a mean of 28.6 years following diagnosis. Three patients underwent TKA at a mean age of 52 years, significantly younger than that observed for primary TKA at our institution (P = 0.004).

CONCLUSIONS

Skeletally immature OCD patients have promising histories, with an estimated 14% risk of persistent knee pain, 6% symptomatic osteoarthritis, and 3% conversion to TKA at 14 years' mean follow-up. Females, patellar lesions, and unstable lesions demonstrated increased persistent knee pain risk. Patients with OCD undergo TKA at a significantly younger age than the general population.

Comparison of autologous osteoperiosteal cylinder and osteochondral graft transplantation in the treatment of large cystic osteochondral lesions of the talus (OLTs): a protocol for a non-inferiority randomised controlled trial

INTRODUCTION

Large cystic osteochondral lesions of the talus (OLTs) have been shown to have inferior clinical outcomes after reparative techniques such as bone marrow stimulation. Autologous osteochondral transplantation has been viewed as an alternative choice for treating these lesions, but donor-site morbidity has limited its application. Excellent clinical outcomes have been shown in repairing these types of lesions with autologous osteoperiosteal grafts, and these outcomes are achieved at a low cost and without donor-site morbidity in the normal knee joint. This will be the first randomised controlled trial to compare the two surgical techniques, and recommendations for the treatment of patients with large cystic OLTs will be provided.

METHODS AND ANALYSIS

A non-inferiority randomised controlled trial will be conducted. A total of 70 participants with clinically diagnosed large cystic OLTs will be randomly allocated to either the experimental group or the control group at a ratio of 1:1. The experimental group will be treated with autologous osteoperiosteal cylinder graft transplantation, while the control group will be treated with autologous osteochondral transplantation. The primary outcome measure will be the American Orthopaedic Foot & Ankle Society Ankle-Hindfoot Score and the Short Form 12 (SF-12) questionnaire. Secondary outcome measures will include the secondary arthroscopy International Cartilage Repair Society score, the Magnetic Resonance Observation of Cartilage Repair Tissue score, the Tegner activity level score, the visual analogue scale, routine X-rays, CT and complications. These parameters will be evaluated preoperatively, as well as at 3, 6, 12, 24, 36 and 60 months postoperatively. In this trial, we hypothesised that both procedures offer good results for the treatment of patients with large cystic OLTs, and occurrence of donor-site morbidity in autologous osteoperiosteal cylinder graft transplantation group is less than that in autologous osteochondral transplantation group.

ETHICS AND DISSEMINATION

The current study was approved by the board of research ethics of Peking University Third Hospital Medical Science Research Ethics Committee. The results of this study will be presented at national and international conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03347877.

Clinical outcome after mosaicplasty of knee articular cartilage defects of patellofemoral joint versus tibiofemoral joint

Background

The purpose was to investigate survival of cartilage repair in the knee joint by osteochondral autograft transfer stratified by location of the lesion; patellofemoral joint (N = 26) versus the medial or lateral femoral condyles (N = 58).

Methods

For survival analyses, “failure” was defined as the event of a patient reporting a poor Lysholm score (below 65 points) or undergoing a knee replacement procedure.

Results

The survival distribution was not significantly different between the patellofemoral joint and the tibiofemoral joint groups.

Conclusions

The current study suggest that similar long-term outcome can be expected after OAT procedures for the patellofemoral or tibiofemoral joint.

Level of evidence

Therapeutic study, Level III.

[Comparison of arthroscopic osteochondral autologous transplantation for articular cartilage injury in young and middle-aged patients]

Objective

To compare the effectiveness of arthroscopic osteochondral autologous transplantation (OAT) in the treatment of young and middle-aged patients with the articular cartilage injury.

Methods

A clinical data of 43 patients (43 knees) with articular cartilage injury, who underwent OAT between January 2008 and August 2016, was retrospectively analyzed. There were 23 patients aged 20-40 years (young group) and 20 patients aged 40-60 years (middle-aged group). The difference in age between the two groups was significant ( t=14.120, P=0.001). There was no significant difference in gender, body mass index, complications, affected side, lesion site, lesion area, and the International Cartilage Repair Society (ICRS) grade of cartilage injury between the two groups ( P>0.05). The function of knee joint was evaluated by Lysholm score and International Knee Documentation Committee (IKDC) score during the follow-up. MRI examination was performed to observe the repair of both receiving and the donor sites.

Results

All the incisions in the two groups were healed by first intention. All patients in the two groups were followed up with an average of 3.6 years (range, 2-8 years). At 2 years after operation, the Lysholm and IKDC scores were significantly improved in the two groups when compared with the preoperative scores ( P<0.05). The Lysholm and IKDC scores in the young group were significantly better than those in the middle-aged group before operation and at 2 years after operation ( P<0.05). However, there was no significant difference in the differences of the Lysholm and IKDC scores between pre- and post-operation between the two groups ( P>0.05). The MRI examination at 2 years after operation showed that both receiving and the donor sites healed well in the two groups.

Conclusion

According to the texture, thickness, elasticity, and lesion area of the cartilage, arthroscopic OAT might be the first choice for the articular cartilage injury in middle-aged patients and can obtain the satisfactory short-term effectiveness.

Osteochondral Autograft Transfer Procedure: Arthroscopic Technique and Technical Pearls

The Osteochondral Autograft Transfer System (OATS; Arthrex, Naples, FL) is an excellent option for the treatment of articular cartilage lesions within the knee. Current literature suggests that at early-term to midterm follow-up, patients experience improved function, alleviation of pain, and good satisfaction with acceptable complication rates. Although long-term data are lacking, studies in athletes have shown that the OATS can provide an adequate rate of return to sports. The OATS procedure has traditionally been considered an open procedure. However, with the advancement of arthroscopic techniques, the procedure can now be completed arthroscopically. We discuss this modern operation.

Patellofemoral Cartilage Repair

Purpose of Review

This review provides an overview of well-established and newly developed cartilage repair techniques for cartilage defects in the patellofemoral joint (PFJ). An algorithm will be presented for approaching cartilage defects considering the distinct anatomy of both the patellar and trochlear articular surfaces.

Recent Findings

Recent studies on cartilage repair in the PFJ have demonstrated improved outcomes in an attempt to delay or obviate the need for arthroplasty, and improve symptoms in young patients. While autologous chondrocyte implantation shows good and excellent outcomes for chondral lesions, osteochondral defects are adequately addressed with osteochondral allograft transplantation. In case of patellar malalignment, concomitant tibial tubercle osteotomy can significantly improve outcomes. Particulated cartilage and bone marrow aspirate concentrate are potential new alternative treatments for cartilage repair, currently in early clinical studies.

Summary

Due to the frequency of concomitant anatomic abnormalities in the PFJ, a thorough clinical examination combined with careful indication for each procedure in each individual patient combined with meticulous surgical technique is central to achieve satisfying outcomes. Additional comparative studies of cartilage repair procedures, as well as investigation of newer techniques, are needed.

Osteochondral Allograft Transplantation of the Knee in Patients Aged 40 Years and Older

BACKGROUND

Treatment of large chondral defects of the knee among patients aged ≥40 years remains a difficult clinical challenge owing to preexisting joint degeneration and the lack of treatment options short of arthroplasty.

PURPOSE

To characterize the survivorship, predictors of failure, and clinical outcomes of osteochondral allograft transplantation (OCA) of the knee among patients aged ≥40 years.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Prospectively collected data were reviewed for 54 consecutive patients aged ≥40 years who were treated with OCA. Preoperative levels of osteoarthritis (according to Kellgren-Lawrence classification) and meniscal volume and quality were graded from review of radiographs and magnetic resonance imaging. Complications, reoperations, and patient responses to validated outcome measures were reviewed. A minimum follow-up of 2 years was required for analysis. Failure was defined by any removal or revision of the allograft or conversion to arthroplasty.

RESULTS

Among 51 patients (mean age, 48 years; range, 40-63 years; 65% male), a total of 52 knees had symptomatic focal cartilage lesions (up to 2 affected areas) that were classified as Outerbridge grade 4 at the time of OCA and did not involve substantial bone loss requiring shell allografts or additional bone grafting. Mean duration of follow-up was 3.6 years (range, 2-11 years). After OCA, 21 knees (40%) underwent reoperation, including 14 failures (27%) consisting of revision OCA (n = 1), unicompartmental knee arthroplasty (n = 5), and total knee arthroplasty (n = 8). Mean time to failure was 33 months, and 2- and 4-year survivorship rates were 88% and 73%, respectively. Male sex (hazard ratio = 4.18, 95% CI = 1.12-27.13) and a higher number of previous ipsilateral knee operations (hazard ratio = 1.70 per increase in 1 surgical procedure, 95% CI = 1.03-2.83) were predictors of failure. A higher Kellgren-Lawrence osteoarthritis grade on preoperative radiographs was associated with higher failure rates in the Kaplan-Meier analysis but not the multivariate model. At final follow-up, clinically significant improvements were noted in the pain (mean score, 47.8 to 67.6) and physical functioning (56.8 to 79.1) subscales of the Short Form-36, as well as the International Knee Documentation Committee subjective form (45.0 to 63.6), Knee Outcome Survey-Activities of Daily Living (64.5 to 80.1), and overall condition statement (4.5 to 6.8) ( P < .001). No significant changes were noted for the Marx Activity Rating Scale (5.1 to 3.9, P = .789).

CONCLUSION

A higher failure rate was found in this series of patients aged ≥40 years who were treated with OCA as compared with other studies of younger populations. However, for select older patients, OCA can be a good midterm treatment option for cartilage defects of the knee.

Osteochondral autograft transplantation for isolated patellofemoral osteoarthritis

BACKGROUND

The purpose of this retrospective study was to evaluate clinical outcomes of osteochondral autograft transplantation (OAT) for isolated patellofemoral (PF) osteoarthritis (OA).

METHODS

OAT was performed in seven patients (six men, one woman; mean age, 61.1years) with isolated PF OA. The mean duration of follow up was 46.9months (range, 24-84months). Clinical outcomes were evaluated preoperatively and postoperatively according to the International Knee Documentation Committee (IKDC) objective score and the knee scoring system of the Japanese Orthopaedic Association (JOA) score. The International Cartilage Repair Society (ICRS) score was recorded in three cases that underwent second-look arthroscopies postoperatively. For morphological evaluation, the Kellgren and Lawrence (KL) classification and the modified magnetic resonance observation of cartilage repair tissue (MOCART) score were used.

RESULTS

The mean IKDC and JOA scores were both significantly improved. The percentage of normal and nearly normal on the IKDC score was increased from 28.6% (2/7) to 85.7% (6/7) (P=0.05). The mean JOA score was improved from 80.0 (range, 65.0-85.0) to 95.0 (range, 90.0-100) (P=0.0008). The mean ICRS scores were 10.3 (nearly normal) in the three cases that underwent second-look arthroscopies postoperatively. Regarding KL classification, the grade was unchanged in five cases (two cases in grade 1, three cases in grade 2) and improved in two cases (from grade 3 to 2, from grade 4 to 3). The mean modified MOCART score was 67.9 (range, 60.0-75) at 12-month follow up. There were no complications, and satisfaction was obtained in all cases. The study design was case series: level IV.

CONCLUSIONS

All clinical scores improved significantly postoperatively. Osteochondral plugs were transplanted perpendicular to the articular surface to obtain good congruity of the repaired articular surface. In this way, OAT is an effective procedure to prevent progression of isolated PF OA.