Cartilage issues in football-today's problems and tomorrow's solutions.

Articular cartilage injury is prevalent in football players and results from chronic joint stress or acute traumatic injuries. Articular cartilage injury can often result in progressive painful impairment of joint function and limit sports participation. Management of articular cartilage injury in athletes aims to return the player to competition, and requires effective and durable joint surface restoration that resembles normal hyaline articular cartilage that can withstand the high joint stresses of football. Existing articular cartilage repair techniques can return the athlete with articular cartilage injury to high-impact sports, but treatment does not produce normal articular cartilage, and this limits the success rate and durability of current cartilage repair in athletes. Novel scientific concepts and treatment techniques that apply modern tissue engineering technologies promise further advancement in the treatment of these challenging injuries in the high demand athletic population. We review the current knowledge of cartilage injury pathophysiology, epidemiology and aetiology, and outline existing management algorithms, developing treatment options and future strategies to manage articular cartilage injuries in football players.

Return to play after thigh muscle injury in elite football players: implementation and validation of the Munich muscle injury classification.

BACKGROUND: Owing to the complexity and heterogeneity of muscle injuries, a generally accepted classification system is still lacking. AIMS: To prospectively implement and validate a novel muscle injury classification and to evaluate its predictive value for return to professional football. METHODS: The recently described Munich muscle injury classification was prospectively evaluated in 31 European professional male football teams during the 2011/2012 season. Thigh muscle injury types were recorded by team medical staff and correlated to individual player exposure and resultant time-loss. RESULTS: In total, 393 thigh muscle injuries occurred. The muscle classification system was well received with a 100% response rate. Two-thirds of thigh muscle injuries were classified as structural and were associated with longer lay-off times compared to functional muscle disorders (p<0.001). Significant differences were observed between structural injury subgroups (minor partial, moderate partial and complete injuries) with increasing lay-off time associated with more severe structural injury. Median lay-off time of functional disorders was 5-8 days without significant differences between subgroups. There was no significant difference in the absence time between anterior and posterior thigh injuries. CONCLUSIONS: The Munich muscle classification demonstrates a positive prognostic validity for return to play after thigh muscle injury in professional male football players. Structural injuries are associated with longer average lay-off times than functional muscle disorders. Subclassification of structural injuries correlates with return to play, while subgrouping of functional disorders shows less prognostic relevance. Functional disorders are often underestimated clinically and require further systematic study.

Terminology and classification of muscle injuries in sport: the Munich consensus statement.

OBJECTIVE: To provide a clear terminology and classification of muscle injuries in order to facilitate effective communication among medical practitioners and development of systematic treatment strategies. METHODS: Thirty native English-speaking scientists and team doctors of national and first division professional sports teams were asked to complete a questionnaire on muscle injuries to evaluate the currently used terminology of athletic muscle injury. In addition, a consensus meeting of international sports medicine experts was established to develop practical and scientific definitions of muscle injuries as well as a new and comprehensive classification system. RESULTS: The response rate of the survey was 63%. The responses confirmed the marked variability in the use of the terminology relating to muscle injury, with the most obvious inconsistencies for the term strain. In the consensus meeting, practical and systematic terms were defined and established. In addition, a new comprehensive classification system was developed, which differentiates between four types: functional muscle disorders (type 1: overexertion-related and type 2: neuromuscular muscle disorders) describing disorders without macroscopic evidence of fibre tear and structural muscle injuries (type 3: partial tears and type 4: (sub)total tears/tendinous avulsions) with macroscopic evidence of fibre tear, that is, structural damage. Subclassifications are presented for each type. CONCLUSIONS: A consistent English terminology as well as a comprehensive classification system for athletic muscle injuries which is proven in the daily practice are presented. This will help to improve clarity of communication for diagnostic and therapeutic purposes and can serve as the basis for future comparative studies to address the continued lack of systematic information on muscle injuries in the literature. WHAT ARE THE NEW THINGS: Consensus definitions of the terminology which is used in the field of muscle injuries as well as a new comprehensive classification system which clearly defines types of athletic muscle injuries. LEVEL OF EVIDENCE: Expert opinion, Level V.

Clinical outcomes assessment for articular cartilage restoration.

The purpose of this article is to provide an overview and perspective of the available options for clinical outcomes evaluation of articular cartilage repair in the knee. A nonsystematic literature review of reported clinical measures for functional, qualitative, and quantitative structural outcomes evaluation after knee articular cartilage repair was performed. Several outcome scores have been validated for articular cartilage repair in the knee with the International Knee Documentation Committee score, Lysholm score, and Knee injury Osteoarthritis Outcome Score being reported most frequently. Activity measures including Tegner and Marx activity scales and the rate of return to sports have direct practical relevance for athletically active patients. Macroscopic and histological assessment provides important structural information about repair cartilage quality and quantity. In addition, magnetic resonance imaging (MRI) outcome scoring and functional MRI are gaining increasing popularity and promise less invasive systematic assessment. In summary, clinical outcome evaluation after cartilage repair can be performed by various established and validated functional outcome instruments as well as several evolving outcome parameters that provide clinically relevant outcome information for researchers, clinicians, and patients.

Local Intraoperative Marrow-Derived Augmentation for Primary Rotator Cuff Repair: An Updated Systematic Review and Meta-analysis of Studies From 2010 to 2022.

Background: Recurrent tears of the rotator cuff pose a substantial problem despite advances in repair technique. Biologic augmentation via marrow stimulation or vented anchors may strengthen the suture-tendon junction and improve healing rates of native tissue, thereby enhancing outcomes of primary surgical repair. Purpose: To provide a focused systematic review and meta-analysis of local, intraoperative marrow-derived augmentation techniques in clinical primary rotator cuff repair. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review of PubMed, Embase, and Cochrane was conducted following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A total of 2131 studies from 2010 to 2022, focused on either marrow stimulation or vented anchors, were isolated and classified as either preclinical or clinical. Meta-analysis was performed for comparative marrow stimulation and vented anchor studies. Heterogeneity was tested through calculation of I 2. Results: A total of 13 clinical studies were included in the review. All 9 comparative studies included in the meta-analysis demonstrated high methodologic quality or a low risk of bias. The pooled retear rate across all 9 clinical studies for patients undergoing marrow stimulation was 11%. For the 5 studies in the meta-analysis, the pooled retear rates were 15% for marrow stimulation and 30% for controls. Meta-analysis demonstrated a significant difference in the overall retear rate that favored marrow stimulation (odds ratio [OR], 0.41; 95% CI, 0.25-0.66; P = .0003; I 2 = 0%). Similarly, meta-analysis of the Constant score at final follow-up demonstrated a statistically significant difference between the 2 groups that favored a higher Constant score in the marrow stimulation group (mean difference, 2.84; 95% CI, 1.02-4.66; P = .002; I 2 = 29%). Vented anchors demonstrated improved ossification and bone density at the anchor site, but no difference in outcomes or retear. Pooled retear rates were 22.5% for vented anchors and 27.8% for controls. Conclusion: Current evidence demonstrates that marrow-stimulation techniques may have a positive impact on healing and retear rate, while vented anchors have a muted impact relative to nonvented anchors. Although available evidence is limited and more research is needed, findings to date suggest that marrow stimulation techniques may be an inexpensive, straightforward technique to consider in qualifying patients to prevent rotator cuff retears.

Evidence for Utilization of Injectable Biologic Augmentation in Primary Rotator Cuff Repair: A Systematic Review of Data From 2010 to 2022.

Background: Biologic healing after rotator cuff repair remains a significant challenge. Injectable biologic augmentation may improve tissue quality at the suture-tendon interface. Purpose: To investigate the effect of injectable biologic supplementation in rotator cuff repair and to assess the quality and adherence to evolving reporting standards. Study Design: Systematic review; Level of evidence, 3. Methods: A systematic review was conducted following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Included were 40 studies: 29 preclinical (in vivo animal models) and 11 clinical. Each clinical study was assessed for quality, risk of bias, and adherence to relevant MIBO (Minimum Information for Studies Evaluating Biologics in Orthopaedics) guidelines. The outcomes of interest were reported load to failure, load to gap, gap size, and stiffness in the preclinical studies, and healing rate and any patient-reported outcome measures in the clinical studies. Results: Injectables reported included growth factors (eg, transforming growth factor-beta 3, erythropoietin), bone marrow-derived mesenchymal stem cells and adipose-derived mesenchymal stem cells (ADSCs), and other agents such as platelet-rich plasma (PRP) and hyaluronic acid. The most common findings for preclinical injectables were increased load to failure (16/29 studies; 55.2%) and improved collagen histological quality (11/29 studies; 37.9%). All 11 clinical studies (10 PRP, 1 ADSC) indicated no adverse events, with similar or improved patient-reported outcomes compared with repairs in the control groups. In 1 study utilizing an innovative delivery technique, a concentrated PRP globule with fibrin matrix was shuttled over a suture to maintain concentrated PRP at the repair site and demonstrated a significant decrease in retears (P = .03) at a 31-month follow-up. A matched-cohort study investigating augmentation with ADSCs demonstrated a significantly lower retear rate in the ADSC-augmented group than the control group at a 28-month follow-up (P < .001). On average, the clinical studies adhered to 66% of relevant MIBO reporting guidelines and had a low risk of bias. Conclusion: Approximately 83% of preclinical studies found a positive biomechanical or histological effect, with no studies showing an overall negative effect. Clinically, utilization of innovative delivery techniques may reduce the risk of arthroscopic washout of PRP and improve retear rates. ADSCs were shown to reduce retear rates at a 28-month follow-up.

Scientific Developments and Clinical Applications Utilizing Chondrons and Chondrocytes with Matrix for Cartilage Repair.

Injuries to articular cartilage of the knee are increasingly common. The operative management of these focal chondral lesions continues to be problematic for the treating orthopedic surgeon secondary to the limited regenerative capacity of articular cartilage. The pericellular matrix (PCM) is a specialized, thin layer of the extracellular matrix that immediately surrounds chondrocytes forming a unit together called the chondron. The advancements in our knowledge base with regard to the PCM/chondrons as well as interterritorial matrix has permeated and led to advancements in product development in conjunction with minced cartilage, marrow stimulation, osteochondral allograft, and autologous chondrocyte implantation (ACI). This review intends to summarize recent progress in chondrocytes with matrix research, with an emphasis on the role the PCM/extracellular matrix (ECM) plays for favorable chondrogenic gene expression, as a barrier/filtration unit, and in osteoarthritis. The bulk of the review describes cutting-edge and evolving clinical developments and discuss these developments in light of underlying basic science applications. Clinical applications of chondrocytes with matrix science include Reveille Cartilage Processor, Cartiform, and ACI with Spherox (which was recently recommended for the treatment of grade III or IV articular cartilage defects over 2 cm2 by the National Institute of Health and Care Excellence [NICE] in the United Kingdom). The current article presents a comprehensive overview of both the basic science and clinical results of these next-generation cartilage repair techniques by focusing specifically on the scientific evolution in each category as it pertains with underlying chondrocytes with matrix theory.

Next-Generation Marrow Stimulation Technology for Cartilage Repair: Basic Science to Clinical Application.

¼: Given the relatively high prevalence of full-thickness articular cartilage lesions, including in patients who are <40 years of age, and an inability to detect some of these lesions until the time of arthroscopy, there is value in performing a single-stage cartilage procedure such as marrow stimulation (MS). ¼: While the positive outcomes of first-generation MS (namely microfracture) have been observed to drop off after 24 months in several studies, improvements have been seen when compared with preoperative conditions for lesions that are 2 to 3 cm2 in size, and MS is considered to be a procedure with technical simplicity, fairly short surgical times, and relatively low morbidity. A recent study showed that autologous chondrocyte implantation (ACI) and osteochondral allograft (OCA) transplantation remain viable treatment options for chondral defects of the knee in the setting of failed MS. ¼: Basic science principles that have been elucidated in recent years include (1) the creation of vertical walls during defect preparation, (2) an increased depth of subchondral penetration, (3) a smaller awl diameter, and (4) an increased number of subchondral perforations, which are all thought to help resolve issues of access to the mesenchymal stromal cells (MSCs) and the subchondral bone structure/overgrowth issues. ¼: Pioneering and evolving basic science and clinical studies have led to next-generation clinical applications, such as a hyaluronic acid-based scaffold (ongoing randomized controlled trial [RCT]), an atelocollagen-based gel (as described in a recently published RCT), a micronized allogeneic cartilage scaffold (as described in a recently completed prospective cohort study), and a biosynthetic hydrogel that is composed of polyethylene glycol (PEG) diacrylate and denatured fibrinogen (as described in an ongoing prospective study). ¼: This review summarizes important points for defect preparation and the recent advances in MS techniques and identifies specific scaffolding augmentation strategies (e.g., mesenchymal augmentation and scaffold stimulation [MASS]) that have the capacity to advance cartilage regeneration in light of recent laboratory and clinical studies.

Current Applications of Growth Factors for Knee Cartilage Repair and Osteoarthritis Treatment.

PURPOSE OF REVIEW: The decreased contact area, edge loading, and increased stress in the adjacent area cartilage resulting from chondral defects are believed to predispose this tissue to degenerative changes that have significant economic implications, especially when considering its progression to osteoarthritis of the knee. Growth factors are considered therapeutic possibilities to enhance healing of chondral injuries and modify the progression to degenerative arthritis. Thus, the purposes of this review are to first to summarize important points for defect preparation and recent advances in techniques for marrow stimulation and second, and to identify specific growth factors and cytokines that have the capacity to advance cartilage regeneration and the treatment of osteoarthritis in light of recent laboratory and clinical studies. RECENT FINDINGS: TGF-ß, BMP-2, BMP-7, IGF-1, as IL-1 receptor antagonist, and recombinant human FGF-18 are some of the promising growth factor/cytokine treatments with pioneering and evolving clinical developments. The bulk of the review describes and discusses these developments in light of fundamental basic science. It is crucial to also understand the other underlying advances made in the surgical management of cartilage defects prior to onset of OA. These advances are in techniques for defect preparation and marrow stimulation, a common cartilage repair procedure used in combination with growth factor/cytokine augmentation. Multiple growth factor/cytokine modulation therapies are currently undergoing clinical trial investigation including Invossa (currently in phase III study), Kineret (currently in phase I study), and Sprifermin (currently in phase II study) for the treatment of symptomatic osteoarthritis.

High Prevalence of Superior Labral Anterior-Posterior Tears Associated With Acute Acromioclavicular Joint Separation of All Injury Grades.

BACKGROUND: Despite the relatively high number of cases of acromioclavicular joint (AC) separation in the athletic population, optimal clinical outcomes are not achieved in every case. Limited data exist regarding the prevalence of intra-articular glenohumeral pathologies (IAPs) associated with acute AC separation of all injury grades. PURPOSE: To determine the prevalence of IAPs associated with AC separation, regardless of severity. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 62 patients (mean age, 37.6 years) with acute AC separation were included in this study; 41 were nonoverhead recreational athletes. All patients underwent magnetic resonance arthrography (MRA) to evaluate for IAPs. Arthroscopic data from patients undergoing surgical treatment were correlated with MRA results. RESULTS: Patients sustained acute AC separation of Rockwood grade 1 (16.1%), grade 2 (46.8%), grade 3 (25.8%), and grade 4 (11.3%). A concomitant IAP was present in 48 of 62 (77.4%) patients and included superior labral anterior-posterior tears (72.6%), anterior labral tears (24.2%), posterior labral tears (4.8%), supraspinatus tears (3.2%), and inferior glenohumeral ligament ruptures (1.6%). There were 18 (29.0%) patients who had a concomitant pathology in >1 intra-articular structure (combined IAPs). Additionally, 71.8% of patients with grade 1 and 2 AC separation had associated IAPs, and 23.1% had combined IAPs. Furthermore, in patients younger than 40 years, 64.0% of those with grade 1 to 3 AC separation demonstrated associated labral pathologies. There was no difference when comparing age or severity of AC separation and the prevalence of concomitant labral tears (P = .36 and .22, respectively). CONCLUSION: There was a high prevalence of IAPs among patients undergoing MRA after AC separation. While an IAP has been described in association with high-grade AC separation previously, the high prevalence of IAPs in low-grade separation in our study was unexpected and suggests that a thorough evaluation and clinical follow-up for patients with all grades of AC separation may be beneficial.

Articular cartilage repair in athletes.

Articular cartilage lesions in the athletic population commonly occur and result from the significant acute and chronic joint stress associated with high-impact sports. These lesions have poor intrinsic healing capacity, and the persistent defects in the joint surfaces cause pain, swelling, and mechanical symptoms that result in functional impairment and limitation of athletic participation. If untreated, articular cartilage lesions can lead to chronic joint degeneration and disability. Several techniques for articular cartilage repair have been recently developed with promising results. However, the significant joint stresses generated in athletes require an effective and durable cartilage surface restoration that can withstand the high mechanical demands in this population over time.

Functional outcome after acute compartment syndrome of the thigh.

BACKGROUND: Acute compartment syndrome of the thigh is an uncommon condition that is associated with a high rate of morbidity. Because of its rarity, limited information is available on the long-term functional outcome for patients with this condition and the factors that affect the clinical result. METHODS: Eighteen patients with acute compartment syndrome of the thigh were evaluated at an average of sixty-two months after treatment. Functional outcome was evaluated by means of physical examination, isokinetic thigh-muscle testing, and validated functional outcome scores. RESULTS: Long-term functional deficits were present in eight patients, and only five patients had full recovery of thigh-muscle strength. The persistent dysfunction was reflected in worse overall functional outcome scores. High injury severity scores, ipsilateral femoral fracture, prolonged intervals to decompression, the presence of myonecrosis at the time of fasciotomy, and an age of more than thirty years were associated with increased long-term functional deficits, persistent thigh-muscle weakness, and worse functional outcome scores. CONCLUSIONS: Acute compartment syndrome of the thigh is often associated with considerable long-term morbidity. Several factors can affect the functional outcome, and knowledge of these factors can help in the development of a more effective clinical management strategy to reduce long-term morbidity.

High-impact athletics after knee articular cartilage repair: a prospective evaluation of the microfracture technique.

BACKGROUND: Knee articular cartilage injuries in athletes present a therapeutic challenge and have been identified as an important cause of permanent disability because of the high mechanical joint stresses in athletes. PURPOSE: To determine whether microfracture treatment of knee articular cartilage injuries can return athletes to high-impact sports and to identify the factors that affect the ability to return to athletic activity. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Thirty-two athletes who regularly participated in high-impact, pivoting sports before articular cartilage injury were treated with microfracture for single articular cartilage lesions of the knee. Functional outcome was prospectively evaluated with a minimum 2-year follow-up by subjective rating, activity-based outcome scores, and the ability for postoperative participation in high-impact, pivoting sports. RESULTS: At last follow-up, 66% of athletes reported good or excellent results. Activity of daily living, Marx activity rating scale, and Tegner activity scores increased significantly after microfracture. After an initial improvement, score decreases were observed in 47% of athletes. Forty-four percent of athletes were able to regularly participate in high-impact, pivoting sports, 57% of these at the preoperative level. Return to high-impact sports was significantly higher in athletes with age <40 years, lesion size <200 mm(2), preoperative symptoms <12 months, and no prior surgical intervention. CONCLUSION: Microfracture is an effective first-line treatment to return young athletes with short symptomatic intervals and small articular cartilage lesions of the knee back to high-impact athletics.

Incidence, Degree, and Clinical Effect of Subchondral Bone Overgrowth After Microfracture in the Knee.

BACKGROUND: Subchondral bone overgrowth has been described with variable frequency after microfracture, but little systematic information is available about the clinical incidence, risk factors, or clinical relevance of this phenomenon. HYPOTHESIS: Subchondral overgrowth (1) occurs with high incidence and various degrees after microfracture, (2) is associated with risk factors, and (3) affects clinical outcome score and failure rate. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 84 patients undergoing microfracture in the knee were prospectively followed up to 6 years postoperatively through use of cartilage-sensitive magnetic resonance imaging to detect the incidence of subchondral bone overgrowth. The quantity of the overgrowth was graded systematically and was then correlated to patient and lesion characteristics, surgical technique, validated functional outcome scores, and failure rate. RESULTS: Subchondral bone overgrowth was observed in 62% of patients at a mean of 22 months after surgery. Most bone overgrowth (64%) was low grade and developed during the first 12 months after microfracture. Risk factors for bone overgrowth included high body mass index, defects on the lateral femoral condyle, and aggressive debridement of the calcified cartilage layer. Knee injury and Osteoarthritis Outcome Score results were not significantly different between patients with or without subchondral bone overgrowth. However, 93% of patients who failed microfracture demonstrated osseous overgrowth, and patients with osseous overgrowth showed a significantly higher failure rate (25%) than patients without overgrowth (3.1%; P < .01). CONCLUSION: Subchondral bone overgrowth is frequently observed after microfracture surgery but is mostly of low grade. Several risk factors were identified that can affect the incidence of this phenomenon. Importantly, subchondral overgrowth is associated with an increased rate of postoperative failure after microfracture.

The microfracture technique for the treatment of articular cartilage lesions in the knee. A prospective cohort study.

BACKGROUND: Microfracture is a frequently used technique for the repair of articular cartilage lesions of the knee. Despite the popularity of the technique, prospective information about the clinical results after microfracture is still limited. The purpose of our study was to identify the factors that affect the clinical outcome from this cartilage repair technique. METHODS: Forty-eight symptomatic patients with isolated full-thickness articular cartilage defects of the femur in a stable knee were treated with the microfracture technique. Prospective evaluation of patient outcome was performed for a minimum follow-up of twenty-four months with a combination of validated outcome scores, subjective clinical rating, and cartilage-sensitive magnetic resonance imaging. RESULTS: At the time of the latest follow-up, knee function was rated good to excellent for thirty-two patients (67%), fair for twelve patients (25%), and poor for four (8%). Significant increases in the activities of daily living scores, International Knee Documentation Committee scores, and the physical component score of the Short Form-36 were demonstrated after microfracture (p < 0.05). A lower body-mass index correlated with higher scores for the activities of daily living and SF-36 physical component, with the worst results for patients with a body-mass index of >30 kg/m(2). Significant improvement in the activities of daily living score was more frequent with a preoperative duration of symptoms of less than twelve months (p < 0.05). Magnetic resonance imaging in twenty-four knees demonstrated good repair-tissue fill in the defect in thirteen patients (54%), moderate fill in seven (29%), and poor fill in four patients (17%). The fill grade correlated with the knee function scores. All knees with good fill demonstrated improved knee function, whereas poor fill grade was associated with limited improvement and decreasing functional scores after twenty-four months. CONCLUSIONS: Microfracture repair of articular cartilage lesions in the knee results in significant functional improvement at a minimum follow-up of two years. The best short-term results are observed with good fill grade, low body-mass index, and a short duration of preoperative symptoms. A high body-mass index adversely affects short-term outcome, and a poor fill grade is associated with limited short-term durability.

Complex articular cartilage restoration.

Articular cartilage injury and degeneration occurs frequently in athletes and results from the significant chronic joint stress and acute traumatic injuries associated with high-impact sports. These injuries do not heal spontaneously and often lead to progressive painful impairment of joint function and limitation of sports participation. Untreated articular cartilage defects frequently lead to chronic joint degeneration and disability. Treatment of articular cartilage injury in athletes can be complex and requires effective and durable joint surface restoration that can withstand even the significant joint stresses generated during sports activity. Several established articular cartilage repair techniques have been shown to successfully return the athlete with articular cartilage injury to high-impact sports. In addition, novel treatment concepts and techniques that apply modern tissue engineering technologies promise further advancement in the treatment of these challenging injuries in the demanding athletic population.

Microfracture in Football (Soccer) Players: A Case Series of Professional Athletes and Systematic Review.

BACKGROUND: Little information is available on the results of microfracture in competitive football (soccer) players. We aimed to evaluate the efficacy of this technique to restore joint function to a level that allows return to this popular high-impact sport. METHODS: This article provides an overview of the basic science and the current published scientific evidence for articular cartilage repair using the microfracture technique in elite football (soccer) athletes. In addition, the senior author documents his results in a case series of professional football (soccer) players treated with microfracture. RESULTS: Twenty-one professional male soccer players underwent microfracture for knee articular cartilage defects. Nineteen players had isolated cartilage injuries, and 2 players had simultaneous anterior cruciate ligament injuries. Average age of the player was 27 years (range, 18-32 years). Twelve players (57%) had single defects, and 9 (43%) had multiple defects. All players complied with the postoperative rehabilitation program. Twenty players (95%) returned to professional soccer the season following microfracture surgery and continued to play for an average of 5 years (range, 1-13 years). Years of continued play inversely correlated with player age at the time of microfracture (r = -0.41). CONCLUSION: Articular cartilage repair with the microfracture technique followed by appropriate rehabilitation provides restoration of knee joint function in professional football (soccer) players with a high rate of return to football (soccer) and continued participation under the significant demands of professional football (soccer). Thorough understanding of the technical aspects, rehabilitation, and literature can help to optimize the results of microfracture in the athletic population.

Return to Sports after Articular Cartilage Repair in the Football (Soccer) Player.

BACKGROUND: The ability to return to football (soccer) presents a critical aspect for successful treatment of articular cartilage injury in the football (soccer) player. METHODS: Information about sports participation after articular cartilage repair was collected from the literature. Special focus was placed on data in football athletes with information on return rate, timing of return, level of postoperative competition, and the ability to compete in the sport over time. RESULTS: Twenty studies describing 1,469 athletes including football players with articular cartilage injury were reviewed. Average return to sport was 79% without a significant difference in return rate or postoperative level of play between cartilage repair techniques. Time to return varied between 7 to 17 months, with the longest time for autologous chondrocyte transplantation (ACI). Advanced sport-specific rehabilitation was able to reduce recovery time. Durability of results was best after ACI, with up to 96% continued sport participation after more than 3 years. Player age, time between injury and treatment, competitive level, defect size, and repair tissue morphology affected the ability to return to play. Sports participation after cartilage repair generally promoted joint restoration and functional recovery. CONCLUSIONS: Articular cartilage repair allows for a high rate of return to high-impact sports including football, often at the preinjury competitive level. The time of return and durability can be variable and depend on repair technique and athlete-specific factors. Advanced, sport-specific rehabilitation can facilitate return to football.

Evolution and Current Role of Autologous Chondrocyte Implantation for Treatment of Articular Cartilage Defects in the Football (Soccer) Player.

BACKGROUND: Autologous chondrocyte implantation (ACI) continues to technically evolve, but how the technical innovations affect the ability to participate in high-impact sports such as football is unknown. METHODS: Clinical studies describing athletes treated with first-, second-, or third-generation ACI techniques were reviewed. The technical developments of ACI were evaluated, and the results in athletes and specifically football (soccer) players were analyzed. RESULTS: Football players reported 72% good to excellent results with significant overall improvement of knee function and activity scores. Return to football was 83% in competitive players but lower in recreational players. Eighty percent of players returned to the same competitive level after ACI, and 87% to 100% maintained their ability to play sports at 5 years postoperatively. Return to sport was better for younger, competitive players with shorter intervals between injury and ACI. New developments of the surgical technique and postoperative rehabilitation were able to reduce the limitations associated with first-generation ACI including invasiveness, graft hypertrophy, and particularly long postoperative rehabilitation. This allowed for faster return to sports like football without compromising the ability for continued competition over time. CONCLUSION: Articular cartilage repair in football players often allows for successful return to this high-impact sport with excellent durability. The continued evolution of this technique has improved initial shortcomings with important implications for both the professional and recreational athlete.

Current concepts for rehabilitation and return to sport after knee articular cartilage repair in the athlete.

Articular cartilage injury is observed with increasing frequency in both elite and amateur athletes and results from the significant acute and chronic joint stress associated with impact sports. Left untreated, articular cartilage defects can lead to chronic joint degeneration and athletic and functional disability. Treatment of articular cartilage defects in the athletic population presents a therapeutic challenge due to the high mechanical demands of athletic activity. Several articular cartilage repair techniques have been shown to successfully restore articular cartilage surfaces and allow athletes to return to high-impact sports. Postoperative rehabilitation is a critical component of the treatment process for athletic articular cartilage injury and should take into consideration the biology of the cartilage repair technique, cartilage defect characteristics, and each athlete's sport-specific demands to optimize functional outcome. Systematic, stepwise rehabilitation with criteria-based progression is recommended for an individualized rehabilitation of each athlete not only to achieve initial return to sport at the preinjury level but also to continue sports participation and reduce risk for reinjury or joint degeneration under the high mechanical demands of athletic activity.