Comparative efficacy of cartilage repair procedures in the knee: a network meta-analysis

PURPOSE

While numerous randomized controlled trials have compared surgical treatments for cartilage defects of the knee, the comparative efficacy of these treatments is still poorly understood. The goal of this network meta-analysis was to synthesize these randomized data into a comprehensive model allowing pairwise comparisons of all treatment options and treatment rankings based on multiple measures of efficacy. We hypothesized that advanced chondral procedures would have improved outcomes when compared to microfracture.

METHODS

The MEDLINE, COCHRANE and EMBASE databases were searched systematically up to January 2015. The primary outcome was re-operation measured at 2, 5 and 10 years. Secondary outcomes included Tegner and Lysholm scores, the presence of hyaline cartilage on post-operative biopsy and graft hypertrophy. A random-effects network meta-analysis was performed, and the results are presented as odds ratios and mean differences with 95 % CIs. We ranked the comparative effects of all treatments with surface under the cumulative ranking probabilities.

RESULTS

Nineteen RCT from 15 separate cohorts including 855 patients were eligible for inclusion. No differences were seen in re-operation rates at 2 years. At 5 years osteochondral autografts (OC Auto) had a lower re-operation rate than microfracture (OR 0.03, 95 % CI 0.00-0.49), and at 10 years OC Auto had a lower re-operation rate than microfracture (OR 0.34, 95 % CI 0.12-0.92), but a higher re-operation rate than second-generation ACI (OR 5.81, 95 % CI 2.33-14.47). No significant differences in Tegner or Lysholm scores were seen at 2 years. Functional outcome data at 5 and 10 years were not available. Hyaline repair tissue was more common with OC Auto (OR 16.13, 95 % CI 2.80-92.91) and 2nd generation ACI (OR 7.69, 95 % CI 1.17-50) than microfracture, though the clinical significance of this is unknown. Second-generation ACI (OR 0.12, 95 % CI 0.02-0.59) and MACI (OR 0.13, 95 % CI 0.03-0.59) had significantly lower rates of graft hypertrophy than first-generation ACI. Second-generation ACI, OC Auto and MACI were the highest ranked treatments (in order) when all outcome measures were included.

CONCLUSIONS

Microfracture and advanced cartilage repair techniques have similar re-operation rates and functional outcomes at 2 years. However, advanced repair techniques provide higher-quality repair tissue and might afford lower re-operation rates at 5 and 10 years.

LEVEL OF EVIDENCE

Meta-analysis studies, Level I.

Autologous-cell-derived, tissue-engineered cartilage for repairing articular cartilage lesions in the knee: study protocol for a randomized controlled trial

Background

Spontaneous recovery from articular cartilage injury is difficult, and the ongoing progression of disease can eventually lead to osteoarthritis. Currently, there is no effective non-surgical treatment for articular cartilage injury. Arthroscopic debridement and microfracture surgery are performed for fibrocartilage repair. But fibrocartilage is different from normal articular cartilage, and functional recovery is not satisfactory. Therefore, it is necessary to develop more effective techniques for articular cartilage repair. Progress in material science, cell biology, biomechanics, and bioreactor technology has allowed the development of biomimetic, tissue-engineered osteochondral composites that have shown potential for the repair of damaged cartilage. We prepared biomimetic, tissue-engineered cartilage scaffolds optimized for biochemical composition and structural characteristics. Based on the experience of our pre-clinical studies on animals, a human articular cartilage acellular matrix scaffold was prepared and is in clinical use. The combination of autologous chondrocytes and scaffolds has shown satisfactory results in repairing cartilage defects in preliminary experiments.

Methods

This is a prospective randomized controlled trial. One hundred patients with full-thickness cartilage injury of the knee will be randomly divided into two groups to receive treatment with either tissue-engineered cartilage constructed using biomimetic cartilage extracellular-matrix-oriented scaffolds combined with autologous chondrocytes, or arthroscopic debridement and microfracture surgery. There will be five visiting time points: at baseline, then at 3, 6, 12, and 18 months postoperatively. The primary outcome will be therapeutic efficacy as assessed by the Lysholm score at 12 months postoperatively. The secondary outcomes will be the International Knee Documentation Committee score, Visual Analog Scale score, and cartilage injury and repair as assessed by magnetic resonance imaging as well as the incidence of postoperative adverse events.

Discussion

This trial will attempt to verify the use of tissue-engineered cartilage constructed using autologous chondrocytes combined with allogeneic, acellular cartilage matrix for the repair of cartilage defects, thereby providing favorable evidence for its use in clinical practice.

Trial registration

ClinicalTrials.gov, identifier: NCT02770209. Registered on 11 May 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2251-6) contains supplementary material, which is available to authorized users.

Augmented cartilage regeneration by implantation of cellular versus acellular implants after bone marrow stimulation: a systematic review and meta-analysis of animal studies

Bone marrow stimulation may be applied to regenerate focal cartilage defects, but generally results in transient clinical improvement and formation of fibrocartilage rather than hyaline cartilage. Tissue engineering and regenerative medicine strive to develop new solutions to regenerate hyaline cartilage tissue. This systematic review and meta-analysis provides a comprehensive overview of current literature and assesses the efficacy of articular cartilage regeneration by implantation of cell-laden versus cell-free biomaterials in the knee and ankle joint in animals after bone marrow stimulation. PubMed and EMBASE (via OvidSP) were systematically searched using tissue engineering, cartilage and animals search strategies. Included were primary studies in which cellular and acellular biomaterials were implanted after applying bone marrow stimulation in the knee or ankle joint in healthy animals. Study characteristics were tabulated and outcome data were collected for meta-analysis for studies applying semi-quantitative histology as outcome measure (117 studies). Cartilage regeneration was expressed on an absolute 0–100% scale and random effects meta-analyses were performed. Implantation of cellular biomaterials significantly improved cartilage regeneration by 18.6% compared to acellular biomaterials. No significant differences were found between biomaterials loaded with stem cells and those loaded with somatic cells. Culture conditions of cells did not affect cartilage regeneration. Cartilage formation was reduced with adipose-derived stem cells compared to other cell types, but still improved compared to acellular scaffolds. Assessment of the risk of bias was impaired due to incomplete reporting for most studies. Implantation of cellular biomaterials improves cartilage regeneration compared to acellular biomaterials.

Return to sport after the surgical management of articular cartilage lesions in the knee: a meta-analysis

PURPOSE

Optimal surgical treatment of chondral defects in an athletic population remains highly controversial and has yet to be determined. The purpose of this review was to (1) report data on return to sport and (2) compare activity and functional outcome measures following various cartilage restoration techniques.

METHODS

A comprehensive review was performed for studies with return-to-sport outcomes after microfracture (MFX), osteochondral autograft transfer (OAT), osteochondral allograft transplantation (OCA), and autologous chondrocyte implantation (ACI). All studies containing return-to-sport participation with minimum 2-year post-operative activity-based outcomes were included. A meta-analysis comparing rate of return to sport between each surgical intervention was conducted using a random-effects model.

RESULTS

Forty-four studies met inclusion criteria (18 Level I/II, 26 Level III/IV). In total, 2549 patients were included (1756 M, 793 F) with an average age of 35 years and follow-up of 47 months. Return to sport at some level was 76 % overall, with highest rates of return after OAT (93 %), followed by OCA (88 %), ACI (82 %), and MFX (58 %). Osteochondral autograft transfer showed the fastest return to sports (5.2 ± 1.8 months) compared to 9.1 ± 2.2 months for MFX, 9.6 ± 3.0 months for OCA and 11.8 ± 3.8 months for ACI (P < 0.001). A meta-regression was conducted due to heterogeneity in preoperative factors such as patient age, lesion size, and preoperative Tegner score. None of these factors were found to be significant determinants for rate of return to sport.

CONCLUSION

In conclusion, in this meta-analysis of 2549 athletes, cartilage restoration surgery had a 76 % return to sport at mid-term follow-up. Osteochondral autograft transfer offered a faster recovery and appeared to have a higher rate of return to preinjury athletics, but heterogeneity in lesion size, athlete age, and concomitant surgical procedures are important factors to consider when assessing individual athletes. This study reports on the rate of return to sport in athletes undergoing various procedures for symptomatic chondral defects.

LEVEL OF EVIDENCE

IV.

Granulocyte macrophage - colony stimulating factor (GM-CSF) significantly enhances articular cartilage repair potential by microfracture

OBJECTIVE

To investigate whether granulocyte macrophage-colony stimulating factor (GM-CSF) can be used to increase the number of mesenchymal stem cells (MSCs) in blood clots formed by microfracture arthroplasty (MFX) and whether it can improve the therapeutic outcome for cartilage repair.

METHODS

Thirty-six New Zealand white rabbits were divided into four groups: (1) control, (2) GM-CSF, (3) MFX, and (4) GM-CSF + MFX. GM-CSF was administrated intravenously (IV) at 10 μg/kg body weight 20 min before the MFX surgery. The repaired tissues were retrieved and examined by histological observation, quantitative assessment, and biochemical assays at 4, 8, and 12 weeks after treatment. The number of MSCs was measured in the blood clots by the colony forming unit-fibroblast (CFU-F) assay. The kinetic profile and distribution of GM-CSF in vivo was also evaluated by near-Infrared (NIR) fluorescence imaging and enzyme-linked immune sorbent assay.

RESULTS

In the histological observations and chemical assays examined at 4, 8, and 12 weeks, the MFX after GM-CSF administration showed better cartilage repair than the one without GM-CSF. The CFU-F assay showed a significantly larger amount of MSCs present in the blood clots of the GM-CSF + MFX group than in the blood clots of the other groups. The blood concentration of GM-CSF peaked at 10 min and decreased back to almost the initial level after a couple of hours. GM-CSF was distributed in many organs including the bone marrow but was not observed clearly in the joint cavity.

CONCLUSION

Intravenous administration of GM-CSF together with MFX could be a promising therapeutic protocol to enhance the repair of cartilage defects.

Surgical treatments of cartilage defects of the knee: Systematic review of randomised controlled trials

BACKGROUND

The aim of this systematic review was to identify high quality randomised controlled trials (RCTs) and to provide an update on the most appropriate surgical treatments for knee cartilage defects.

METHODS

Two reviewers independently searched three databases for RCTs comparing at least two different treatment techniques for knee cartilage defects. The search strategy used terms mapped to relevant subject headings of MeSH terms. Strict inclusion and exclusion criteria were used to identify studies with patients aged between 18 and 55 years with articular cartilage defects sized between one and 15cm². Risk of bias was performed using a Coleman Methodology Score. Data extracted included patient demographics, defect characteristics, clinical outcomes, and failure rates.

RESULTS

Ten articles were included (861 patients). Eight studies compared microfracture to other treatment; four to autologous chondrocyte implantation (ACI) or matrix-induced ACI (MACI); three to osteochondral autologous transplantation (OAT); and one to BST-Cargel. Two studies reported better results with OAT than with microfracture and one reported similar results. Two studies reported superior results with cartilage regenerative techniques than with microfracture, and two reported similar results. At 10years significantly more failures occurred with microfracture compared to OAT and with OAT compared to ACI. Larger lesions (>4.5cm²) treated with cartilage regenerative techniques (ACI/MACI) had better outcomes than with microfracture.

CONCLUSIONS

Based on the evidence from this systematic review no single treatment can be recommended for the treatment of knee cartilage defects. This highlights the need for further RCTs, preferably patient-blinded, using an appropriate reference treatment or a placebo procedure.

Comparison of distraction arthroplasty alone versus combined with arthroscopic microfracture in treatment of post-traumatic ankle arthritis

Background

This study aims to compare clinical outcomes of distraction arthroplasty alone versus combined with arthroscopic microfracture in treating post-traumatic ankle arthritis.

Methods

The study cohort consisted of 96 patients (96 ankles) who underwent distraction arthroplasty alone or combined with arthroscopic microfracture between May 2005 and April 2012. Patients were divided into the distraction group (n = 46) and the combined group (n = 50). The American Orthopaedic Foot and Ankle Society (AOFAS) score, visual analog scale (VAS), and ankle activity score (AAS) were used to compare the clinical outcomes between groups. Arthritis severity was assessed on the radiograph.

Results

At the mean follow-up period of 30.8 ± 3.1 and 31.4 ± 3.6 months, respectively, no severe complications occurred and no further surgical interventions for symptomatic arthritis were required in both groups. The AOFAS scores improved significantly in the combined group than in the distraction group (59.0 ± 4.7 and 58.0 ± 4.9 preoperatively versus 85.0 ± 4.9 and 88.9 ± 5.4 at final visit, P < 0.001). The AAS scores were also significantly higher in the combined group (3.6 ± 1.1 and 3.3 ± 1.0 preoperatively versus 6.5 ± 1.1 and 7.1 ± 1.3 at final visit, P = 0.009). Pain was significantly alleviated in the combined group by the VAS scores (6.4 ± 0.9 and 6.7 ± 0.9 preoperatively versus 2.3 ± 0.8 and 2.0 ± 0.7 at final visit, P = 0.040). The combined group achieved better radiographic arthritis severity decrease than the distraction group (P = 0.012).

Conclusions

Compared to distraction arthroplasty alone, distraction arthroplasty combined with arthroscopic microfracture can offer better functional recovery, pain relief, and ankle arthritis resolution for treating post-traumatic ankle arthritis.

The effect of systemic administration of G-CSF on a full-thickness cartilage defect in a rabbit model MSC proliferation as presumed mechanism: G-CSF for cartilage repair

Objectives

The aim of this study was to investigate the effect of granulocyte-colony stimulating factor (G-CSF) on mesenchymal stem cell (MSC) proliferation in vitro and to determine whether pre-microfracture systemic administration of G-CSF (a bone marrow stimulant) could improve the quality of repaired tissue of a full-thickness cartilage defect in a rabbit model.

Methods

MSCs from rabbits were cultured in a control medium and medium with G-CSF (low-dose: 4 μg, high-dose: 40 μg). At one, three, and five days after culturing, cells were counted. Differential potential of cultured cells were examined by stimulating them with a osteogenic, adipogenic and chondrogenic medium.

A total of 30 rabbits were divided into three groups. The low-dose group (n = 10) received 10 μg/kg of G-CSF daily, the high-dose group (n = 10) received 50 μg/kg daily by subcutaneous injection for three days prior to creating cartilage defects. The control group (n = 10) was administered saline for three days. At 48 hours after the first injection, a 5.2 mm diameter cylindrical osteochondral defect was created in the femoral trochlea. At four and 12 weeks post-operatively, repaired tissue was evaluated macroscopically and microscopically.

Results

The cell count in the low-dose G-CSF medium was significantly higher than that in the control medium. The differentiation potential of MSCs was preserved after culturing them with G-CSF.

Macroscopically, defects were filled and surfaces were smoother in the G-CSF groups than in the control group at four weeks. At 12 weeks, the quality of repaired cartilage improved further, and defects were almost completely filled in all groups. Microscopically, at four weeks, defects were partially filled with hyaline-like cartilage in the G-CSF groups. At 12 weeks, defects were repaired with hyaline-like cartilage in all groups.

Conclusions

G-CSF promoted proliferation of MSCs in vitro. The systemic administration of G-CSF promoted the repair of damaged cartilage possibly through increasing the number of MSCs in a rabbit model.

Cite this article: T. Sasaki, R. Akagi, Y. Akatsu, T. Fukawa, H. Hoshi, Y. Yamamoto, T. Enomoto, Y. Sato, R. Nakagawa, K. Takahashi, S. Yamaguchi, T. Sasho. The effect of systemic administration of G-CSF on a full-thickness cartilage defect in a rabbit model MSC proliferation as presumed mechanism: G-CSF for cartilage repair. Bone Joint Res 2017;6:123–131. DOI: 10.1302/2046-3758.63.BJR-2016-0083.

A randomized controlled trial demonstrating sustained benefit of Autologous Matrix-Induced Chondrogenesis over microfracture at five years

PURPOSE

Autologous Matrix-Induced Chondrogenesis (AMIC^®) utilizing a type I/III collagen membrane was compared with microfracture (MFx) alone in focal cartilage lesions of the knee at one, two and five years.

METHODS

Forty-seven patients (aged 37 ± 10 years, mean defect size 3.6 ± 1.6 cm²) were randomized and treated either with MFx, with sutured or glued AMIC^® in a prospective multicentre clinical trial.

RESULTS

After improvement for the first two years in all subgroups, a progressive and significant score degradation was observed in the MFx group, while all functional parameters remained stable for least five years in the AMIC^® groups. At two and five years, MRI defect filling was more complete in the AMIC^® groups. No treatment-related adverse events were reported.

CONCLUSIONS

AMIC^® is an effective cartilage repair procedure in the knee resulting in stable clinical results significantly better than the MFx group at five years.

A randomized controlled trial demonstrating sustained benefit of Autologous Matrix-Induced Chondrogenesis over microfracture at five years

PURPOSE

Autologous Matrix-Induced Chondrogenesis (AMIC^®) utilizing a type I/III collagen membrane was compared with microfracture (MFx) alone in focal cartilage lesions of the knee at one, two and five years.

METHODS

Forty-seven patients (aged 37 ± 10 years, mean defect size 3.6 ± 1.6 cm²) were randomized and treated either with MFx, with sutured or glued AMIC^® in a prospective multicentre clinical trial.

RESULTS

After improvement for the first two years in all subgroups, a progressive and significant score degradation was observed in the MFx group, while all functional parameters remained stable for least five years in the AMIC^® groups. At two and five years, MRI defect filling was more complete in the AMIC^® groups. No treatment-related adverse events were reported.

CONCLUSIONS

AMIC^® is an effective cartilage repair procedure in the knee resulting in stable clinical results significantly better than the MFx group at five years.

[Arthroscopic treatment of chondral lesions of the ankle joint. Evidence-based therapy]

Ankle sprains are the most relevant injuries of the lower extremities and can lead to damage to ligaments and osteochondral lesions. Up to 50 % of patients with a sprained ankle later develop a lesion of the cartilage in the ankle joint or an osteochondral lesion of the talus. This can lead to osteoarthritis of the injured ankle joint. Spontaneous healing is possible in all age groups in cases of a bone bruise in the subchondral bone but in isolated chondral injuries is only useful in pediatric patients. In many cases chondral and osteochondral injuries lead to increasing demarcation of the affected area and can result in progressive degeneration of the joint if not recognized in time. There also exist a certain number of osteochondral changes of the articular surface of the talus without any history of relevant trauma, which are collectively grouped under the term osteochondrosis dissecans. Perfusion disorders are discussed as one of many possible causes of these alterations. Nowadays, chondral and osteochondral defects can be treated earlier due to detection using very sensitive magnetic resonance imaging (MRI) and computed tomography (CT) techniques. The use of conservative treatment only has a chance of healing in pediatric patients. Conservative measures for adults should only be considered as adjuvant treatment to surgery.Based on a comprehensive analysis of the current literature, this article gives an overview and critical analysis of the current concepts for treatment of chondral and osteochondral injuries and lesions of the talus. With arthroscopic therapy curettage and microfracture of talar lesions are the predominant approaches or retrograde drilling of the defect is another option when the chondral coating is retained. Implantation of autologous chondral cells or homologous juvenile cartilage tissue is also possible with arthroscopic techniques. Osteochondral fractures (flake fracture) are usually performed as a mini-open procedure supported by arthroscopy. The use of the osteochondral autograft transfer system (OATS), implantation of membranes with or without autologous bone marrow transfer and possibly with growth factors or implantation of stem cells are carried out in combination with arthroscopic mini-open procedures. The results from the literature are discussed and compared with own results after arthroscopic treatment of chondral lesions of the talus.

Spontaneous Osteonecrosis of the Knee: A Retrospective Analysis by Using MRI and DEXA

Objective:

Although there are many etiology and prediction for prognosis of spontaneous osteonecrosis of the knee (SONK) by using radiological examinations, these issue have not been clarified yet. Furthermore, most of the studies evaluated them by only radiological examination such as magnetic resonance imaging (MRI), bone mineral density (BMD) in dual-energy X-ray abosorptiometry (DEXA) or plain X-ray. Therefore, we focused our investigation on the measurements of the affected área in MRI and BMD in DEXA, and whether these results were conected with the cause and prognosis of SONK or not.

Method:

A consecutive case series of two groups composed of ten osteoporotic patients who were suffering from SONK was considered. Based on the severity or duration of pain, one group was treated with surgical procedure which was unicompartmental knee arthroplasty (UKA), the other received conservative treatment. Both groups underwent DEXA in their distal fêmur and próximal tíbia and all patients who took MRI measured the affected lesion in low and high intensity área on T2 weighted images. This data was analyzed from these areas and units.

Results:

Significant decrease in regional boné density of the affected femoral condyle compared to the unaffected side was observed. However, the boné mineral density in the affected side was similar in the non-operative and surgical group. The área of the lesion which showed in both low and high intensity indicated that the operation group was significantly larger than the conservative group on T2 weighted images.

Conclusion:

The cause and prognosis of SONK have a close relationship with the size of the affected lesion and decreased boné mineral density

Arthroscopic Management of Osteochondral Lesions of the Talus

Osteochondral fractures of the ankle are typically caused by traumatic injuries of the ankle. Repetitive trauma can lead to further cartilage damage with subsequent increasing size of the lesion, ultimately leading to severe cartilage disorder and degenerative arthritis of the ankle. Arthroscopic bone marrow stimulation has been shown to be a highly successful option for patients with small osteochondral lesions. Studies show a higher failure rate for larger lesions and cystic changes that disrupt the subchondral plate. The threshold size seems to be 150 mm(2).

Cartilage repair strategies in the knee: A survey of Turkish surgeons

Objectives

The purpose of this study was to analyze the trends in cartilage repair strategies among Turkish orthopedic surgeons for isolated focal (osteo)chondral lesions of the knee joint.

Materials and methods

A web-based survey of 21 questions consisting of surgical indications, techniques and time to return to sports was developed to investigate the preferences of members of the TOTBID and the TUSYAD.

Results

A total of 147 surgeons answered the questionnaire.70% of the respondents were TUSYAD members. 82% of respondents had at least five years experience in arthroscopy. Half of the surgeons indicated that patient age of 50 was the upper limit for cartilage repair. Irrespective of activity level, microfracture (60–67%) was the most frequently used technique for lesions smaller 2.5 cm². In lesions larger than 4 cm², MACI was the most commonly advocated procedure (67%). In patients with high activity levels, mosaicplasty was the first choice (69%) for lesions between 2.5 and 4 cm² in size, followed by MACI (27%).

Conclusion

Patient age, activity level, BMI and lesion size were important determinants for the choice of treatment of isolated chondral lesions in the knee. These results reflect the choices of experienced knee surgeons in the country. Although not widely performed in Turkey and has limited reimbursement by the health care system, the first choice for defects over 4 cm² was second generation ACI. Third party payers & health reimbursement authorities should take into account that large defects require methods which are relatively expensive and need high technology. Cross-sectional survey, Level II.

Improved cartilage regeneration by implantation of acellular biomaterials after bone marrow stimulation: a systematic review and meta-analysis of animal studies

Microfracture surgery may be applied to treat cartilage defects. During the procedure the subchondral bone is penetrated, allowing bone marrow-derived mesenchymal stem cells to migrate towards the defect site and form new cartilage tissue. Microfracture surgery generally results in the formation of mechanically inferior fibrocartilage. As a result, this technique offers only temporary clinical improvement. Tissue engineering and regenerative medicine may improve the outcome of microfracture surgery. Filling the subchondral defect with a biomaterial may provide a template for the formation of new hyaline cartilage tissue. In this study, a systematic review and meta-analysis were performed to assess the current evidence for the efficacy of cartilage regeneration in preclinical models using acellular biomaterials implanted after marrow stimulating techniques (microfracturing and subchondral drilling) compared to the natural healing response of defects. The review aims to provide new insights into the most effective biomaterials, to provide an overview of currently existing knowledge, and to identify potential lacunae in current studies to direct future research. A comprehensive search was systematically performed in PubMed and EMBASE (via OvidSP) using search terms related to tissue engineering, cartilage and animals. Primary studies in which acellular biomaterials were implanted in osteochondral defects in the knee or ankle joint in healthy animals were included and study characteristics tabulated (283 studies out of 6,688 studies found). For studies comparing non-treated empty defects to defects containing implanted biomaterials and using semi-quantitative histology as outcome measure, the risk of bias (135 studies) was assessed and outcome data were collected for meta-analysis (151 studies). Random-effects meta-analyses were performed, using cartilage regeneration as outcome measure on an absolute 0–100% scale. Implantation of acellular biomaterials significantly improved cartilage regeneration by 15.6% compared to non-treated empty defect controls. The addition of biologics to biomaterials significantly improved cartilage regeneration by 7.6% compared to control biomaterials. No significant differences were found between biomaterials from natural or synthetic origin or between scaffolds, hydrogels and blends. No noticeable differences were found in outcome between animal models. The risk of bias assessment indicated poor reporting for the majority of studies, impeding an assessment of the actual risk of bias. In conclusion, implantation of biomaterials in osteochondral defects improves cartilage regeneration compared to natural healing, which is further improved by the incorporation of biologics.

Microfracture for chondral defects: assessment of the variability of surgical technique in cadavers

PURPOSE

The purpose of this study was to assess the variability of the microfracture technique when performed by experienced knee arthroscopy surgeons.

METHOD

Four surgeons were each asked to perform microfracture on six preformed cartilage defects in fresh human cadaveric knees. Surgeons were instructed on penetration depth, inter-hole distance, and to place the holes perpendicular to the subchondral surface. Micro-computed tomography was used to calculate depth error, inter-hole distance error, and deviation of penetration angles from the perpendicular.

RESULTS

All surgeons misjudged depth and inter-hole distance, tending to make microfracture holes too deep (depth error 1.1 mm ± 1.9) and too close together (inter-hole distance error: -0.8 mm ± 0.4). Fifty-one per cent of holes were angled more than 10° from the perpendicular (range 2.6°-19.8°). Both depth and distance errors were significantly lower in the trochlear groove than on the femoral condyle (p < 0.05). Surface shearing was associated with both penetration depth >4 mm and angles >20°. Inter-hole infraction occurred in holes closer than 2.5 mm to each other.

CONCLUSION

Even experienced knee arthroscopy surgeons demonstrate inconsistency in surgical technique when performing microfracture. While further research will be required to demonstrate that these variations in surgical technique are associated with poorer clinical outcomes after microfracture, surgeons should attempt to minimizing such variations in order to prevent surface shearing and inter-hole infraction.

Comparison of clinical outcomes between arthroscopic subchondral drilling and microfracture for osteochondral lesions of the talus

PURPOSE

The objectives of this study were to compare the clinical outcomes of the two common bone marrow stimulation techniques such as subchondral drilling and microfracture for symptomatic osteochondral lesions of the talus and to evaluate prognostic factors affecting the outcomes.

METHODS

Ninety patients (90 ankles) who underwent arthroscopic bone marrow stimulation for small- to mid-sized osteochondral lesions of the talus constituted the study cohort. The 90 ankles were divided into two groups: a drilling group (40 ankles) and a microfracture group (50 ankles). Each group was matched for age and gender, and both groups had characteristics similar to those obtained from pre-operative demographic data. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and the ankle activity score (AAS) were used to compare clinical outcomes, during a mean follow-up period of 43 months.

RESULTS

The median AOFAS scores were 66.0 points (51-80) in drilling group and 66.5 points (45-81) in microfracture group pre-operatively, and these improved to 89.4 points (77-100) and 90.1 points (69-100) at the final follow-up, respectively. The median VAS scores improved at the final follow-up compared with the pre-operative condition. The median AAS for the drilling group improved from 4.5 (1-6) pre-operatively to 6.0 (1-8) at the final follow-up, while those for the microfracture group improved from 3.0 (2-8) to 6.0 (3-9). No significant differences were observed between the two groups in terms of the AOFAS scores, VAS, and AAS.

CONCLUSIONS

The arthroscopic subchondral drilling and microfracture techniques that were used to stimulate bone marrow showed similar clinical outcomes. The results of this study suggest that both techniques are effective and reliable in treating small- to mid-sized osteochondral lesions of the talus, regardless of which of the two techniques is used.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Osteochondritis dissecans of the elbow

Capitellar osteochondritis dissecans (OCD) can be a significant problem in adolescent overhead athletes. The cause is likely multifactorial secondary to repetitive stresses, biomechanical mismatch, and a tenuous vascular supply of the capitellum. Recent literature reveals that the prevalence is likely higher than previously thought. This, in conjunction with increased levels of athletic competition in children at younger ages, has fed the recent interest in this topic. The literature continues to show that non-operative treatment is still successful for stable lesions. Unstable lesions, therefore, have been the focus of the new literature regarding operative management and outcomes. The aim of this paper is to provide a summary of current literature and an up-to-date approach to the diagnosis, evaluation, and treatment of osteochondritis dissecans of the capitellum.

Correlation between histological outcome and surgical cartilage repair technique in the knee: A meta-analysis

BACKGROUND

Compare histological outcomes after microfracture (MF), autologous chondrocyte implantation (ACI), and osteochondral autograft transfer (OATS).

METHODS

Literature review using PubMed MEDLINE, SCOPUS, Cumulative Index for Nursing and Allied Health Literature (CINAHL), and Cochrane Collaboration Library. Inclusion criteria limited to English language studies International Cartilage Repair Society (ICRS) grading criteria for cartilage analysis after ACI (autologous chondrocyte implantation), MF (microfracture), or OATS (osteochondral autografting) repair techniques.

RESULTS

Thirty-three studies investigating 1511 patients were identified. Thirty evaluated ACI or one of its subtypes, six evaluated MF, and seven evaluated OATS. There was no evidence of publication bias (Begg's p=0.48). No statistically significant correlation was found between percent change in clinical outcome and percent biopsies showing ICRS Excellent scores (R(2)=0.05, p=0.38). Percent change in clinical outcome and percent of biopsies showing only hyaline cartilage were significantly associated (R(2)=0.24, p=0.024). Mean lesion size and histological outcome were not correlated based either on percent ICRS Excellent (R(2)=0.03, p=0.50) or percent hyaline cartilage only (R(2)=0.01, p=0.67). Most common lesion location and histological outcome were not correlated based either on percent ICRS Excellent (R(2)=0.03, p=0.50) or percent hyaline cartilage only (R(2)=0.01, p=0.67).

CONCLUSIONS

Microfracture has poorer histologic outcomes than other cartilage repair techniques. OATS repairs primarily are comprised of hyaline cartilage, followed closely by cell-based techniques, but no significant difference was found cartilage quality using ICRS grading criteria among OATS, ACI-C, MACI, and ACI-P.

LEVEL OF EVIDENCE

IV, meta-analysis.

Can chondral healing be improved following microfracture? The effect of adipocyte tissue derived stem cell therapy

BACKGROUND

We aimed to investigate the effect of adipose tissue-derived mesenchymal stem cells (ADSCs) on chondral healing using the microfracture (MF) technique.

METHODS

Thirty male rabbits were randomly divided into three groups. Standard cylindrical osteochondral defects (OCDs) were created in the weight-bearing areas of the medial condyles of all the right knees; the defects were four millimeters in diameter and two millimeters in depth. The control group (group A) was restricted to spontaneous healing. For group B, we performed MF with a 1.5-mm drill. For group C, we applied MF using the same method and then applied 3×10(6) ADSCs to the defect area. At eight weeks post-operation, the subjects were sacrificed, and the distal femoral joint surfaces were evaluated histopathologically for chondral healing. The samples were scored according to the International Cartilage Repair Society (ICRS) scale.

RESULTS

The results for group C were significantly better than those for group A in terms of the surface properties (p=0.003). The matrix evaluation was better for group A than for group C (p=0.01). The cell distribution, cell viability and subchondral bone parameters were similar between the groups (p=0.198, p=0.387 and p=0.699). The cartilage mineralization parameter was better for group C than for group A (p=0.001). The signs of healing were better for group C than for group B, but the differences were not significant (p=0.185).

CONCLUSIONS

Improvements with additional ADSC treatments were not statistically significant in cases in which ADSC treatment was compared with isolated MF treatment.

CLINICAL RELEVANCE

Additional ADSCs treatment may have positive effect on chondral healing but it doesn't seem significant.

Chondral and osteochondral operative treatment in early osteoarthritis

In recent years treatment of early osteoarthritis came more and more into focus of orthopaedic research. In particular regenerative therapy options seem to have a high potential to fill the existing treatment gap for patients with early osteoarthritic changes. This article focuses on basic science, recent developments and available clinical data in the important field of operative regeneration procedures for treatment of chondral and osteochondral defects in early degenerative joints. It highlights current knowledge and perspectives of treatment options like microfracture, autologous or allogenous osteochondral transplantations and autologous chondrocyte transplantation. Further the role of biomaterials in a degenerative joint environment is illuminated. First clinical data of regenerative therapy in early osteoarthritis are encouraging to intensify research efforts in this important field. Future treatment perspectives for patients who suffer from early degenerative cartilage changes are discussed.

Results at 10-14 years after microfracture treatment of articular cartilage defects in the knee

PURPOSE

To evaluate the long-term clinical outcome after microfracture treatment of focal chondral defects of the knee and to investigate possible early determinants of the outcome.

METHODS

A prospective cohort of 110 patients, treated with microfracture, was evaluated at a median of 12 years (range 10-14) by Lysholm score, VAS of knee function and VAS of knee pain. Pre- and perioperative information was collected, and additional surgery to the same knee during the follow-up period was recorded. Analysis of variance and paired t test were used for comparison of the long-term data to results from the baseline examination and a former 5-year (midterm) follow-up evaluation.

RESULTS

Forty-three patients needed additional surgery to the knee including seven knee replacements. Fifty had a poor long-term outcome-defined as a knee replacement surgery or Lysholm score below 64. A poor result was more common in subgroups with mild degenerative changes in the cartilage surrounding the treated defect, concurrent partial meniscectomy, poor baseline Lysholm score or long-standing knee symptoms. The Lysholm score, function VAS and pain VAS all significantly improved from the baseline values to the mean scores of 65 (SD 24), 65 (SD 24) and 31 (SD 24), respectively, at the long-term evaluation. The long-term scores did not differ significantly from the midterm scores.

CONCLUSIONS

The outcome scores improved significantly from baseline to the long-term evaluation and were not different from the midterm outcome. Still, a normal knee function was generally not achieved, and many patients had further surgery. The results call for more research and, at present, caution in recommending microfracture in articular cartilage defects, especially in subgroups with worse prognosis.

LEVEL OF EVIDENCE

Case series, Level IV.

Clinical and MRI outcomes of HA injection following arthroscopic microfracture for osteochondral lesions of the talus

PURPOSE

The purpose of this study was to compare the clinical and magnetic resonance imaging (MRI) outcomes of arthroscopic microfracture surgery alone or in combination with hyaluronic acid (HA) injection in the treatment of osteochondral lesions of the talus.

METHODS

Thirty-five patients with osteochondral lesions of the talus who underwent arthroscopic microfracture were included and followed up for at least 9 months post-operatively. The patients were randomly divided into non-injection group (n = 17) who received treatment with microfracture surgery alone and injection group (n = 18) who also accepted intra-articular injection of HA post-operatively. Quantitative MRI was used to evaluate the cartilage repair after surgery. American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hind foot Scale scores and Visual Analogue Scale (VAS) scores were used to evaluate clinical outcomes.

RESULTS

After operation, the MRI outcomes showed that the thickness index was higher (0.8 ± 0.1 vs. 0.7 ± 0.1) and the T2 index was lower (1.2 ± 0.1 vs. 1.4 ± 0.1) in the injection group than in the non-injection group (P < 0.01). As for the volumes of subchondral bone marrow oedema, there are no significant differences between groups (n.s.). Compared with the non-injection group, the AOFAS score and the VAS score yielded a higher level of improvement in injection group at final follow-up post-operatively (P < 0.05).

CONCLUSIONS

Arthroscopic microfracture is a safe and effective procedure for osteochondral lesions of the talus. Intra-articular HA injection as an adjunct to arthroscopic microfracture might offer better functional recovery than microfracture alone.

LEVEL OF EVIDENCE

II.

Long-term results of microfracture in the treatment of talus osteochondral lesions

PURPOSE

Osteochondral lesions of the talus are common injuries, and many clinicians consider arthroscopic debridement and microfracture as the first-stage treatment. This study assessed the long-term clinical and radiographic outcomes of arthroscopic debridement and microfracture for osteochondral lesions of the talus.

METHODS

A total of 82 patients (48 males, 34 females) who were treated with arthroscopic debridement and microfracture for osteochondral lesions of the talus between 1996 and 2009 with a minimum 5-year follow-up were included in our study group. Functional scores (AOFAS, VAS) and ankle range of motion were determined, and an arthrosis evaluation was performed. Subgroup evaluations based on age, lesion localization, and defect size were performed using functional outcome correlations.

RESULTS

The mean age of the patients was 35.9 ± 13.4 years (14-69 years), and the mean follow-up period was 121.3 months (61-217 months). The mean defect size was 1.7 ± 0.7 cm2 (0.25-5). The mean pre-operative AOFAS score was 58.7 ± 5.2 (49-75), and the mean post-operative AOFAS score was 85.5 ± 9.9 (56-100). At the last follow-up, 35 patients (42.6%) had no symptoms and 19 patients (23.1%) had pain after walking more than 2 h or after competitive sports activities. Radiological assessments of arthrosis revealed that no patient had grade 4 arthritis but that 27 patients (32.9%) had a one-stage increase in their arthrosis level. Subgroup analyses of the lesion location demonstrated that lateral lesions had significantly better functional results (p = 0.02).

CONCLUSIONS

Arthroscopic debridement and microfracture provide a good option for the treatment of osteochondral lesions of the talus over the long term in select patients. Functional outcomes do not correlate with defect size or patient age. Orthopaedic surgeons should adopt the microfracture technique, which is minimally invasive and effective for treating osteochondral lesions of the talus.

LEVEL OF EVIDENCE

IV.

Study of Imaging Pattern in Bone Marrow Oedema in MRI in Recent Knee Injuries and its Correlation with Type of Knee Injury

INTRODUCTION

The knee is a major weight bearing joint that provides mobility and stability during physical activity as well as balance while standing. If the knee is exposed to forces beyond its physiologic range, risk of injury to bone or soft tissue structures increases. A thorough understanding of knee injury patterns and their mechanisms may help in achieving more accurate assessment of injuries.

AIM

To identify imaging pattern in bone marrow oedema and to correlate the pattern of bone marrow oedema retrospectively with type of knee injury from clinical history.

MATERIALS AND METHODS

A cross-sectional study was done on all patients referred to Krishna Hospital, Karad for MRI knee with history of recent (< 6 weeks) knee injury. Study was conducted between May 2014 to September 2015 with a sample size of 200 patients. Plain radiograph of knee was done in all patients and they were scanned using 1.5 Tesla Seimens Avanto (Tim + Dot) with Tx/Rx 15 channel knee coil # Tim.

RESULTS

Among the 200 cases, bone marrow contusion was noted in 138 cases (69%) and absent contusion in 62 cases (31%). Bone marrow contusion showed five patterns (according to Sanders classification) i.e., Clip injury in 39 cases (28.3%), Pivot shift injury in 78 cases (56.5%), Dashboard injury in eight cases (5.8%), Hyperextension injury in four cases (2.9%), Lateral patellar dislocation in three cases (2.2%). In six cases (4.3%) no pattern of bone marrow contusion could be explained and was categorized as unclassified pattern.

CONCLUSION

Pivot shift pattern is most common contusion pattern and the most common type/mode of sports related injury. By analysing bone marrow contusion pattern, type/mode can be determined in most of the cases. By applying a biomechanical approach in MR interpretation, it is possible to detect lesions like ligament rupture and osseous contusion, to predict subtle but it might overlook important abnormalities.