Juvenile osteochondritis dissecans

Physician preferences in diagnostics and treatment of juvenile osteochondritis dissecans are diverse across the knee, ankle and elbow: an ESSKA survey

PURPOSE

To investigate the current preferences regarding the work-up and treatment choices of juvenile osteochondritis dissecans (JOCD) of the knee, ankle and elbow among orthopaedic surgeons.

METHODS

An international survey was set up for all European Society of Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA) members, which assessed various questions on diagnosis and treatment of JOCD of different joints. Respondents answered questions for one or more joints, based on their expertise. Proportions of answers were calculated and compared between joints. Consensus was defined as more than 75% agreement on an item; disagreement was defined as less than 25% agreement.

RESULTS

Fifty physicians responded to the survey, of whom forty-two filled out the questions on the knee, fourteen on the ankle and nine on the elbow. Plain radiography and MRI were the most used imaging modalities for the assessment and follow-up of JOCD in the knee and ankle, but not for the elbow. MRI was also the preferred method to assess the stability of a lesion in the knee and ankle. There was universal agreement on activity and/or sports restriction as the non-operative treatment of choice for JOCD. Size, stability and physeal closure were the most important prognostic factors in determining the operative technique for the elbow. For the knee, these factors were size and stability and for the ankle, these were size and location.

CONCLUSION

Activity and/or sports restriction was the non-operative treatment of choice. Furthermore, plain radiography and MRI were the preferred imaging modalities for the knee and ankle, but not for the elbow. For determining the operative technique, physicians agreed that the size of the lesion is an important prognostic factor in all joints. These findings help us understand how juvenile osteochondritis dissecans is treated in current practice and may provide opportunities for improvement.

LEVEL OF EVIDENCE

Level V.

Physeal fusion status and lesion size are more important than patient age for healing of juvenile osteochodritis dessicans lesions of the distal femur

PURPOSE

The purpose of the study was to evaluate the effect of skeletal age and lesion size, location, and grade on the success of nonoperative treatment for juvenile osteochondritis dissecans (OCD). It is hypothesized that skeletal maturity, including a combination of maturation phenotypes, correlates with nonoperative lesion healing.

METHODS

The clinical and radiographic data on 52 patients aged 7-20 years treated for OCD of the distal femur between 2010 and 2019 were retrospectively reviewed. Knee radiographs were assessed for number of lesions present and lesion location, size, and stage. Assessments of skeletal maturation were performed on all antero-posterior knee radiographs using the Roche, Wainer, and Thissen (RWT) method. Patients were categorized as healed if they demonstrated no pain on clinical examination. The relationship between skeletal maturity and nonoperative lesion healing was determined using Spearman rank correlations on available variables.

RESULTS

Neither chronological nor skeletal age was associated with surgical status (Rho = 0.03, n.s., and Rho = 0.13, n.s., respectively) or the healing status of nonoperatively treated OCD lesions (Rho = 0.44, n.s., and Rho = 0.03, n.s., respectively). Epiphyseal fusion status of the distal femoral physis was moderately correlated with nonoperative healing, but was not statistically significant (lateral femoral physis: Rho = 0.43, p = 0.05; medial femoral physis: Rho = 0.43, n.s.). Lesion length correlated with surgical status (Rho = - 0.38, p = 0.009).

CONCLUSION

The extent of fusion of the distal femoral physis (multi-stage grading) may be more strongly correlated with nonoperative healing than other markers of skeletal maturity or chronological age. Clinicians can use this as an additional radiographic sign when considering nonoperative treatment for juvenile OCD lesions in the distal femur. OCD lesion length and physeal fusion status appear to be more important for healing than patient age.

Imaging Review of Normal and Abnormal Skeletal Maturation

The growing skeleton undergoes well-described and predictable normal developmental changes, which may be misinterpreted a as pathologic condition at imaging. Primary and secondary ossification centers (SOCs), which form the diaphysis and the epiphysis of long bones, respectively, are formed by endochondral and intramembranous ossification processes. During skeletal maturation, the SOCs may appear irregular and fragmented, which should not be confused with fractures, osteochondritis dissecans, and osteochondrosis. These normal irregularities are generally symmetric with a smooth, round, and sclerotic appearance, which are aspects that help in the differentiation. The metaphysis, epiphysis, and growth plates or physes are common sites of injuries and normal variants in the pediatric skeleton. The metaphysis contains the newly formed bone from endochondral ossification and is highly vascularized. It is predisposed to easy spread of infections and bone tumors. The physis is the weakest structure of the immature skeleton. Injuries to this location may disrupt endochondral ossification and lead to growth disturbances. Pathologic conditions of the epiphyses may extend into the articular surface and lead to articular damage. At MRI, small and localized foci of bone marrow changes within the epiphysis and metaphysis are also a common finding. These can be related to residual red marrow (especially in the metaphysis of long bones and hindfoot), focal periphyseal edema (associated with the process of physeal closure), and ultimately to a normal ossification process. The authors review the imaging appearance of normal skeletal maturation and discuss common maturation disorders on the basis of developmental stage and location. ^©RSNA, 2022.

Osteochondritis Dissecans: Current Understanding of Epidemiology, Etiology, Management, and Outcomes

➤

Osteochondritis dissecans occurs most frequently in the active pediatric and young adult populations, commonly affecting the knee, elbow, or ankle, and may lead to premature osteoarthritis.

➤

While generally considered an idiopathic phenomenon, various etiopathogenetic theories are being investigated, including local ischemia, aberrant endochondral ossification of the secondary subarticular physis, repetitive microtrauma, and genetic predisposition.

➤

Diagnosis is based on the history, physical examination, radiography, and advanced imaging, with elbow ultrasonography and novel magnetic resonance imaging protocols potentially enabling early detection and in-depth staging.

➤

Treatment largely depends on skeletal maturity and lesion stability, defined by the presence or absence of articular cartilage fracture and subchondral bone separation, as determined by imaging and arthroscopy, and is typically nonoperative for stable lesions in skeletally immature patients and operative for those who have had failure of conservative management or have unstable lesions.

➤

Clinical practice guidelines have been limited by a paucity of high-level evidence, but a multicenter effort is ongoing to develop accurate and reliable classification systems and multimodal decision-making algorithms with prognostic value.

Spontaneous dog osteoarthritis - a One Medicine vision

Osteoarthritis (OA) is a global disease that, despite extensive research, has limited treatment options. Pet dogs share both an environment and lifestyle attributes with their owners, and a growing awareness is developing in the public and among researchers that One Medicine, the mutual co-study of animals and humans, could be beneficial for both humans and dogs. To that end, this Review highlights research opportunities afforded by studying dogs with spontaneous OA, with a view to sharing this active area of veterinary research with new audiences. Similarities and differences between dog and human OA are examined, and the proposition is made that suitably aligned studies of spontaneous OA in dogs and humans, in particular hip and knee OA, could highlight new avenues of discovery. Developing cross-species collaborations will provide a wealth of research material and knowledge that is relevant to human OA and that cannot currently be obtained from rodent models or experimentally induced dog models of OA. Ultimately, this Review aims to raise awareness of spontaneous dog OA and to stimulate discussion regarding its exploration under the One Medicine initiative to improve the health and well-being of both species.

Osteoarthritis occurs spontaneously in pet dogs, which often share environmental and lifestyle risk-factors with their owners. This Review aims to stimulate cooperation between medical and veterinary research under the One Medicine initiative to improve the welfare of dogs and humans.

Dogs have many analogous spontaneous diseases that result in end-stage osteoarthritis (OA).

Inbreeding and the predisposition of certain dog breeds for OA enable easier identification of candidate genetic associations than in outbred humans.

Dog OA subtypes offer a potential stratification rationale for aetiological differences and alignment to analogous human OA phenotypes.

The relatively compressed time course of spontaneous dog OA offers longitudinal research opportunities.

Collaboration with veterinary researchers can provide tissue samples from early-stage OA and opportunities to evaluate new therapeutics in a spontaneous disease model.

Awareness of the limitations and benefits of using clinical veterinary patients in research is important.

Three-Dimensional Quantitative Magnetic Resonance Imaging of Epiphyseal Cartilage Vascularity Using Vessel Image Features: New Insights into Juvenile Osteochondritis Dissecans

We introduce a quantitative measure of epiphyseal cartilage vascularity and examine vessel networks during human skeletal maturation. Understanding early morphological changes in the distal femoral condyle is expected to provide information on the pathogenesis of developmental diseases such as juvenile osteochondritis dissecans.

Methods

Twenty-two cadaveric knees from donors ranging from 1 month to 10 years of age were included in the study. Images of bone, cartilage, and vascularity were acquired simultaneously with a 3-dimensional gradient-recalled-echo magnetic resonance imaging (MRI) sequence. The secondary ossification center volume and total epiphysis cartilage volume ratio and articular-epiphyseal cartilage complex and epiphyseal cartilage widths were measured. Epiphyseal cartilage vascularity was visualized for 9 data sets with quantitative susceptibility mapping and vessel filtering, resulting in 3-dimensional data to inform vessel network segmentation and to calculate vascular density.

Results

Three distinct, non-anastomosing vascular networks (2 peripheral and 1 central) supply the distal femoral epiphyseal cartilage. The central network begins regression as early as 3 months and is absent by 4 years. From 1 month to 3 years, the ratio of central to peripheral vascular area density decreased from 1.0 to 0.5, and the ratio of central to peripheral vascular skeletal density decreased from 0.9 to 0.6. A narrow, peripheral vascular rim was present at 8 years but had disappeared by 10 years. The secondary ossification center progressively acquires the shape of the articular-epiphyseal cartilage complex by 8 years of age, and the central areas of the medial and lateral femoral condyles are the last to ossify.

Conclusions

Using cadaveric pediatric knees, we provide quantitative, 3-dimensional measures of epiphyseal cartilage vascular regression during skeletal development using vessel image features. Central areas with both early vascular regression and delayed ossification correspond to predilection sites of juvenile osteochondritis dissecans in this limited case series. Our findings highlight specific vascular vulnerabilities that may lead to improved understanding of the pathogenesis and better-informed clinical management decisions in developmental skeletal diseases.

Clinical Relevance

This paradigm shift in understanding of juvenile osteochondritis dissecans etiology and disease progression may critically impact future patient management. Our findings highlight specific vascular vulnerabilities during skeletal maturation in a group of active young patients seen primarily by orthopaedic surgeons and sports medicine professionals.

Juvenile osteochondritis dissecans of the knee is a result of failure of the blood supply to growth cartilage and osteochondrosis

OBJECTIVE

Juvenile osteochondritis dissecans (JOCD) is similar to osteochondrosis dissecans (OCD) in animals, which is the result of failure of the cartilage canal blood supply, ischemic chondronecrosis and delayed ossification, or osteochondrosis. The aim of the current study was to determine if osteochondrosis lesions occur at predilection sites for JOCD in children.

METHOD

Computed tomographic (CT) scans of 23 knees (13 right, 10 left) from 13 children (9 male, 4 female; 1 month to 11 years old) were evaluated for lesions consisting of focal, sharply demarcated, uniformly hypodense defects in the ossification front. Histological validation was performed in 11 lesions from eight femurs.

RESULTS

Thirty-two lesions consisting of focal, uniformly hypodense defects in the ossification front were identified in the CT scans of 14 human femurs (7 left, 7 right; male, 7-11 years old). Defects corresponded to areas of ischemic chondronecrosis in sections from all 11 histologically validated lesions. Intra-cartilaginous secondary responses comprising proliferation of adjacent chondrocytes and vessels were detected in six and two lesions, whereas intra-osseous responses including accumulation of chondroclasts and formation of granulation tissue occurred in 10 and six lesions, respectively. One CT cyst-like lesion contained both a pseudocyst and a true cyst in histological sections.

CONCLUSION

Changes identical to osteochondrosis in animals were detected at predilection sites for JOCD in children, and confirmed to represent failure of the cartilage canal blood supply and ischemic chondronecrosis in histological sections.

Bilateral Bicondylar Osteochondritis Dissecans in a Child with Spastic Diplegia and Crouch Gait: A Case Report

CASE

The cause of osteochondritis dissecans is unknown. Various hypotheses suggest mechanical, ischemic, and hereditary causes. We describe a 13-year-old girl with spastic diplegia, a form of cerebral palsy, who had an associated crouch gait and presented with bilateral osteochondral defects of the medial and lateral femoral condyles.

CONCLUSION

This case highlights the potential role of repetitive microtrauma, likely due to the poor biomechanical forces in a crouch gait, and provides support for a mechanical cause of osteochondritis dissecans.

The Surgical Management of Osteochondritis Dissecans of the Knee in the Skeletally Immature: A Survey of the Pediatric Orthopaedic Society of North America (POSNA) Membership

BACKGROUND

While the characteristics of osteochondritis dissecans (OCD) of the knee that require surgery to heal have been described, several surgical techniques/procedures exist with no consensus established regarding timing of treatment and specific surgical intervention. In this study, we aim to determine current trends in surgical treatment for OCD lesions in the skeletally immature who have failed 6 months of nonoperative management by surveying a large cohort of orthopaedic surgeons.

METHODS

An electronic survey designed using REDCap to capture surgeon treatment preferences for OCD lesions was distributed to members of the Pediatric Orthopaedic Society of North America (POSNA). The survey inquired about treating physicians' training and demographics. It then offered a series of clinical vignettes alongside imaging describing patients with varying degrees of severity of OCD following nonoperative treatment. Surgeons were prompted to select from a variety of multiple-choice-based options for further patient management. Standard descriptive statistics were used to summarize and compare the responses.

RESULTS

Of the 129 POSNA members completing the pediatric survey, 97.7% were attending level orthopaedic surgeons, the majority identifying with an academic institution and treating mostly skeletally immature patients. In the skeletally immature population, the majority would treat intact, stable OCD lesions with drilling in a retroarticular or transarticular manner. Preferred treatment for unstable, salvageable lesions was screw fixation using bioabsorble materials or metal with variable pitch with no bone graft. The majority of respondents would treat unstable, unsalvageable OCD lesions with chondroplasty and osteochondral transplant/transfer or microfracture/drilling.

CONCLUSIONS

The POSNA membership appears to agree on principle in terms of treatment modalities for various stages of OCD lesions in the skeletally immature, whereas individual techniques of achieving these principles may vary. Members endorse drilling for stable intact lesions; fixation for unstable, salvageable lesions; and "defect fill" for unsalvageable lesions.

CLINICAL SIGNIFICANCE

OCD surgical treatment patterns can be used in future studies to determine which techniques are most effective for given indications, with the goal of designing a research-proven optimal treatment regimen for skeletally immature patients.

Candidate Loci are Revealed by an Initial Genome-wide Association Study of Juvenile Osteochondritis Dissecans

BACKGROUND

Osteochondritis dissecans (OCD) is a condition that oftentimes causes significant knee pain in pediatric patient populations. If left untreated, OCD significantly increases the risk of developing degenerative osteoarthritis along with its associated consequences and costs. Although a genetic component has been suggested to play a role in this disorder, few studies have been carried out in order to determine the underlying genetic etiology of this relatively common complex trait. The goal of our study was to perform an initial genome-wide association study (GWAS) to uncover candidate loci associated with the pathogenesis of OCD.

METHODS

Blood samples were acquired from 2 cohorts, aged 0 to 18 years old, consisting of 209 OCD cases and 1855 population-matched controls. Agencourt Genfind DNA isolation technology was used to isolate high-quality DNA from each sample. Genotype data was then generated utilizing the Illumina Infinium BeadChip array to examine single-nucleotide polymorphisms (SNPs).

RESULTS

In an initial GWAS analysis of our cohort, where a SNP was excluded if the Hardy-Weinberg Equilibrium test P<0.0001, the minor allele frequency<5%, and the genotyping call rate<90%, we obtained our first results for OCD. Although there was no SNP strictly reaching the threshold for genome-wide significance at this early stage, multiple SNPs (35) at several loci revealed evidence of suggestive association with OCD (P<5.0×10).

CONCLUSIONS

The results from our preliminary study are encouraging. Herein we not only discuss the relevance and applicability of GWAS in studying a genetic basis for OCD, but have also identified top signals that may suggest loci involved in coordinated expression as well as a transcription factor involved in development that may be highly relevant to this trait.

CLINICAL RELEVANCE

If genetic predispositions for OCD are detected early enough in life, attempts at activity modification, counseling, and orthopaedic monitoring may successfully reduce progression of this condition, which may lead to progressive osteoarthritis in the third to fourth decade in at-risk patients.

Repetitive Stresses Generate Osteochondral Lesions in Skeletally Immature Rabbits

BACKGROUND

The origin of juvenile osteochondritis dissecans (OCD) is unknown. Existing experimental animal models of OCD most frequently involve surgically created lesions but do not examine repetitive stress as a possible cause of OCD.

HYPOTHESIS

Repetitive stresses can cause OCD-like lesions in immature animals.

STUDY DESIGN

Controlled laboratory study.

METHODS

Six juvenile rabbits were subjected to repetitive loading forces of approximately 160% body weight to the right hindlimb during five 45-minute sessions per week for 5 weeks. The contralateral limb was the unloaded control. After 5 weeks, rabbits were euthanized and examined with radiographs, micro-computed tomography, and gross and histopathologic analysis.

RESULTS

All 6 rabbits developed osteochondral lesions in loaded limbs on the medial and lateral femoral condyles, while contralateral unloaded limbs did not demonstrate lesions. Loaded limbs developed relative osteopenia in the femoral epiphysis and tibial metaphysis with associated decreased trabecular density. Loaded limbs also demonstrated increased femoral subchondral bone thickness near the lesions. Lesions did not have grossly apparent extensive articular cartilage damage; however, cartilage thickness increased on histology with reduced ossification. Loaded knees demonstrated abundant chondrocyte cloning, limited cartilage fissuring, and a focal loss of cellularity at the articular surface.

CONCLUSION

Low-grade lesions in human OCD have little gross articular cartilage involvement despite substantial changes to the subchondral bone as shown on magnetic resonance imaging and radiographs. Histopathology findings in this study included cartilage thickening and chondrocyte cloning resembling those of recently published human OCD biopsy studies. Our animal model supports the hypothesis that repetitive stress to immature knees may contribute to the development of human OCD. This model may be useful in understanding the pathophysiology and healing of human OCD.

CLINICAL RELEVANCE

Repetitive physiologic stress generated changes to the subchondral bone in immature animals without causing extensive articular damage. The similarities of these lesions in gross and histologic appearance with human OCD support repetitive stress as the likely the cause for human OCD.

Diseases of Subchondral Bone 1

The subchondral zone plays an important role in both the structural and biochemical maintenance of articular cartilage. Knowledge of the structure, function, and pathophysiology of the normal subchondral bone/articular surface interface is essential for an understanding of the pathogenesis of many of the disease entities that we will review in this chapter.

Osteochondritis Dissecans of the Knee in Children and Adolescents: Our Experience with Transchondral Drilling

Osteochondritis dissecans(OCD) of the knee is identified with increasing frequency in the adolescent patient. Left untreated, OCD can cause significant impairment and restriction in physical activity and development of osteoarthritis at an early age. The diagnosis of lesions of OCD can be confirmed on plain radiographs. MRI has emerged as the gold standard to evaluate the stability of the lesion and the integrity of the overlying articular cartilage. Treatment of OCD lesions depend on the stability of the lesion. Stable lesions can be treated conservatively by physical activity modification and immobilization. Unstable lesions and stable lesions not responding to conservative measures should be treated surgically. Surgical options range from arthroscopic drilling, either transarticular or extra-articular drilling for stable lesions or salvage procedures such as autologous chondrocyte transplantation (ACT), mosaicplasty to restore joint and cartilage congruency.

Intact bone vitality and increased accumulation of nonmineralized bone matrix in biopsy specimens of juvenile osteochondritis dissecans: a histological analysis

BACKGROUND

Although commonly proposed to be the starting point of juvenile osteochondritis dissecans (JOCD), avascular osteonecrosis (AVN) has been an inconsistent finding in histological studies. Analysis of early-stage lesions is required to elucidate the origins of OCD and justify proper treatment.

PURPOSE

To analyze histological sections of JOCD lesions with special emphasis on bone vitality.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Of 64 patients with 74 JOCD lesions (20 females, mean age, 11.4 years; 44 males, mean age, 12.7 years), 34 required surgery because of lesion instability or failed nonoperative treatment. From 9 patients, 11 histological specimens were obtained. Lesions were classified according to the International Cartilage Repair Society (ICRS). Two additional histological control sections were harvested from children without JOCD manifestation. Undecalcified histological sections were histomorphometrically analyzed. To analyze the skeletal health of the patients, biochemical analyses with special emphasis on bone metabolism were performed.

RESULTS

Histologically, no osteonecrosis was visible in any of the cases. Osteocyte distribution was similar among OCD lesions and controls. ICRS OCD I lesions (n = 6) showed no intralesional separation. In ICRS OCD II and III lesions (n = 5), there was a subchondral fracture concomitant with histological characteristics of active repair mechanism (increased bone formation: osteoid volume P = .008, osteoblast number P = .046; resorption: osteoclast number P = .005; and tissue fibrosis compared with controls). Instead, in ICRS OCD I lesions, subchondral osteoid volume (P = .010) and osteoblast number (P = .046) were significantly increased compared with controls; however, no active repair mechanisms (no increased bone resorption or fibrous tissue) were detected, suggesting a focal lack of mineralization. Fifty-seven of 64 patients (89.1%) showed a vitamin D deficiency. The median vitamin D serum level of the patients with ICRS OCD I lesions was 13.6 µg/L.

CONCLUSION

In the present study, osteonecrosis was not found in histological specimens of JOCD. As a secondary finding, focal accumulations of nonmineralized bone matrix indicating a lack of mineralization in ICRS OCD I lesions were revealed. This finding correlated with a low level of vitamin D in the affected children.

Surgical management of osteochondritis dissecans lesions of the patella and trochlea in the pediatric and adolescent population

BACKGROUND

There is a paucity of published data regarding the management of osteochondritis dissecans (OCD) lesions of the patellofemoral joint in children and adolescents.

PURPOSE

To evaluate the functional outcomes of surgical management of OCD lesions of the patella and trochlea in children and adolescents. Secondary aims included elucidating predictors for higher functional outcomes and determining complication rates, surgical satisfaction, and ability to return to sports.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients aged 18 years and younger who were surgically treated for OCD of the patella or trochlea were identified. Charts were queried to record patient/lesion data, surgical procedure, results, and complications. Pre- and postoperative imaging was reviewed. Patients were asked to complete a follow-up athletic questionnaire and a Pediatric International Knee Documentation Committee (Pedi-IKDC) questionnaire. Statistical analysis was conducted to look for predictors for reoperation, residual pain, ability to return to sports, and lower Pedi-IKDC scores.

RESULTS

A total of 26 children (9 females, 17 males, 3 with bilateral lesions; thus, 29 lesions) were identified. The mean age was 14.7 years (range, 9-18, years), 21 of the 29 knees with lesions (72%) had open physes, and median follow-up was 3.8 years (range, 1-9 years). The most common location was the trochlea (17/29 lesions; 59%). Twenty-two lesions (76%) underwent transarticular drilling (n = 14) or drilling with fixation (n = 8), while 7 underwent excision and marrow stimulation. Four patients (14%) required unplanned reoperation. Internal fixation was predictive of reoperation (odds ratio [OR] = 8.7; 95% CI, 2.8-26.9; P = .04). At final follow-up, 14 knees (48%) were pain free, and 14 (48%) had mild residual pain. Female sex was predictive of residual pain (OR, 9; 95% CI, 2-56; P = .02). Twenty-two patients (85%) returned to sports. Longer duration of preoperative pain negatively affected return to sports (OR, 0.32; 95% CI, 0.05-0.97; P = .04). On postoperative MRI, the lesion appeared completely healed in 2 cases (18%) and partially healed in 9 cases (82%). All 15 survey respondents were satisfied with surgery. The mean Pedi-IKDC score was 82.4 ± 17.8 (range, 40.2-100).

CONCLUSION

Surgical treatment of patellofemoral OCD in children and adolescents produces a high rate of satisfaction and return to sports. Female sex, prolonged duration of symptoms, and internal fixation may be associated with worse outcomes.

Treatment of juvenile osteochondritis dissecans of the talus: current concepts review

Juvenile osteochondritis dissecans of the talus (JODT) affects the subchondral bone primarily and, in a skeletally immature population, articular cartilage secondarily. It probably consists of aseptic bone necrosis whose spontaneous healing is impaired by microtraumas, resulting in an osteochondral injury and, in some cases, in osteoarthritis. In many cases the clinical presentation is asymptomatic. Mild chronic pain is frequent, sometimes accompanied by swelling, stiffness or locking. Few data are currently available on this topic and, moreover, most existing data were obtained from mixed groups and populations; it is therefore difficult to outline a scheme for the treatment of JODT. However, the most suitable treatment in the first stages of the disease is conservative. The presence of a loose body is an indication for surgical fixation, drilling or regenerative procedures, depending on the presence/extent of subchondral bone sclerosis and the surgeon's experience. Drilling has been shown to promote the healing of lesions with minimal surgical trauma. Microfractures, since they induce fibrocartilage repair, are to be considered only for small injuries. Mosaicplasty and osteochondral autograft transplantation may cause donor site morbidity and are techniques little reported in JODT. Regenerative techniques and fresh allografts give good results in osteochondral lesions, but further studies are required to describe the results that can be obtained in JODT alone.

Meniscal suturing versus screw fixation for treatment of osteochondritis dissecans: clinical and magnetic resonance imaging results

PURPOSE

The purpose of this study was to compare meniscal stabilization alone with screw fixation in restoring subjective and objective knee function and structural cartilage integrity in skeletally immature patients with osteochondritis dissecans (OCD) of the knee.

METHODS

This study comprised 28 patients (32 knees) with magnetic resonance imaging (MRI)-confirmed OCD. Unstable menisci were treated with either stabilization (15 patients, 16 knees) or screw fixation (13 patients, 16 knees; control group). Patients were assessed by functional scoring (Hughston, International Knee Documentation Committee [IKDC]) and MRI for a minimum follow-up period of 2.5 years.

RESULTS

In the meniscus stabilization group, the Hughston score improved from 1.4 to 3.8 (P < .01). There was improvement in the IKDC grade, from grade C preoperatively to grade A in 14 knees and grade B in 2 (P < .01). Of 16 knees, 15 had complete defect resolution on MRI by 1 year. There were 3 complications: 1 wound infection, 1 case of trauma requiring reoperation, and 1 revision because of treatment failure at 6 months. In the screw fixation group, the Hughston score improved from 1.4 to 3.6 (P < .01). There was a significant improvement in IKDC grade, from grade C preoperatively to grade A in 11 knees and grade B in 5 (P < .01). At 2 years postoperatively, no differences in these variables were found between the groups.

CONCLUSIONS

Meniscal suturing alone for the treatment of an OCD of the knee shows good or excellent results in terms of clinical scoring and MRI assessment at almost 3 years' follow-up. The results are comparable with those of screw fixation but with a faster recovery in the postoperative course.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Trochlear groove osteochondritis dissecans of the knee patellofemoral joint

BACKGROUND

The trochlear groove is the rarest location for osteochondritis dissecans (OCD) of the knee, with only about 50 previously reported cases, most of which were treated before the advent of magnetic resonance imaging (MRI) and modern techniques of cartilage fixation or osteochondral transplantation. The purpose of this multicenter study was to assess the patient presentation and clinical, radiographic, and functional results of treatment for trochlear groove OCD lesions.

METHODS

Hospital records from 5 institutions of the Research in Osteochondritis of the Knee (ROCK) study group were retrospectively reviewed for cases of trochlear groove OCD. Demographics, clinical presentation, diagnosis, treatment, time to pain resolution, and return to sports were recorded. Lesion appearance, size, stability, and time to radiographic healing were evaluated on plain x-rays and MRIs.

RESULTS

Trochlear groove OCD lesions were evaluated in 24 knees in 21 adolescents (17 male, 4 female), with an average age of 14 years (range, 10 to 18 y). Fifty-four percent (13/24) of the lesions were identifiable on radiographs, and all were identifiable on MRI, 38% of which (9/24) was unstable. One fourth (6/24) of knees had coexistent femoral condyle OCD lesions. Treatment outcomes were evaluated in patients with a minimum of 1-year follow-up (average: 3 y; range: 1 to 12 y) or healing before 1 year. Half of the knees (2/4) treated nonoperatively and two thirds (8/12) treated operatively showed radiographic signs of healing with patients returning to full activity without pain. Operative treatment success rates were as follows: drilling (3/3), fixation (3/3), microfracture (1/2), drilling with subsequent delayed microfracture (1/1), and drilling with fixation (0/3).

CONCLUSIONS

MRI aids in the diagnosis and staging of trochlear groove OCD lesions, as almost one half may not be identifiable on radiographs, and one quarter are associated with OCD lesions in other locations of the same knee. Multiple operative treatments can be used to achieve healing or resolution of symptoms in stable and unstable lesions; however, a larger comparative study is needed to make specific recommendations.

LEVEL OF EVIDENCE

Therapeutic Level IV.

Management strategies for osteochondritis dissecans of the knee in the skeletally immature athlete

SYNOPSIS

Osteochondritis dissecans (OCD) is a disorder resulting in focal breakdown of the subchondral bone, with potential disruption of the overlying articular cartilage. The femoral condyles of the knee are the most common locations for OCD, and the incidence of OCD appears to be increasing among active children. Juvenile OCD (JOCD) can be distinguished from adult OCD by the presence of open growth plates. Due to a lack of evidence on its early diagnosis, optimal treatment, and long-term course of healing, JOCD presents a unique challenge for the health care team. Approximately 50% to 67% of stable JOCD lesions heal successfully with nonoperative treatment. For unstable lesions and stable lesions that fail nonoperative treatment, a variety of surgical interventions can be utilized to stimulate bony healing and address articular cartilage lesions. It is recommended that rehabilitation of JOCD be tailored to the individual patient, based on the stage and radiographic status of the lesion and the mode of surgery employed when surgically addressed. Although there is a growing body of literature on this condition, the etiology and optimal methods for treatment, rehabilitation, and evaluating outcomes remain inconclusive due to a lack of quality evidence.

LEVEL OF EVIDENCE

Therapy, level 5.

The demographics and epidemiology of osteochondritis dissecans of the knee in children and adolescents

BACKGROUND

Osteochondritis dissecans (OCD) is a disorder of subchondral bone and articular cartilage whose incidence in children is not clearly known.

PURPOSE

The purpose of this study was to assess the demographics and epidemiology of OCD of the knee in children.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

A retrospective chart review of an integrated health system was performed on patients with OCD of the knee aged 2 to 19 years from 2007 to 2011, with over 1 million patients in this cohort. Lesion location, laterality, and all patient demographics were recorded. The incidence of OCD was determined for the group as a whole and by sex and age group (2-5 years, 6-11 years, and 12-19 years). Patient differences based on age, sex, and ethnicity were analyzed, and using multivariable logistic regression models, associations between age, sex, ethnicity, and diagnosis of OCD of the knee were evaluated.

RESULTS

One hundred ninety-two patients with 206 OCD lesions of the knee fit the inclusion criteria. No OCD lesion of the knee was found in 2- to 5-year-old children. One hundred thirty-one (63.6%) lesions were in the medial femoral condyle, 67 (32.5%) were in the lateral femoral condyle, 96 (50.0%) lesions were right sided, 82 (42.7%) were left sided, and 14 (7.3%) were bilateral. The incidence of patients with OCD of the knee aged 6 to 19 years was 9.5 per 100,000 overall and 15.4 and 3.3 per 100,000 for male and female patients, respectively. Those aged 12 to 19 years represented the vast majority of OCD, with an incidence of 11.2 per 100,000 versus 6.8 per 100,000 for those aged 6 to 11 years. For those aged 6 to 11 and 12 to 19 years, female patients had an incidence of 2.3 and 3.9 per 100,000, respectively, while male patients had an incidence of 11.1 and 18.1 per 100,000, respectively. Multivariable logistic regression analysis revealed a 3.3-fold increased risk of OCD of the knee in patients aged 12 to 19 years compared with those aged 6 to 11 years (P < .001; 95% confidence interval [CI], 2.37-4.48), and male patients had 3.8 times a greater risk of OCD of the knee than female patients (P < .001; 95% CI, 2.71-5.41). Based on race and ethnicity, blacks had the highest odds ratio of OCD of the knee compared with all other ethnic groups.

CONCLUSION

In this population-based cohort study of pediatric OCD of the knee, male patients had a much greater incidence of OCD and almost 4 times the risk of OCD compared with female patients. Also, patients aged 12 to 19 years had 3 times the risk of OCD of the knee as compared with 6- to 11-year-old children.

Articular osteochondrosis: a comparison of naturally-occurring human and animal disease

BACKGROUND

Osteochondrosis (OC) is a common developmental orthopedic disease affecting both humans and animals. Despite increasing recognition of this disease among children and adolescents, its pathogenesis is incompletely understood because clinical signs are often not apparent until lesions have progressed to end-stage, and examination of cadaveric early lesions is not feasible. In contrast, both naturally-occurring and surgically-induced animal models of disease have been extensively studied, most notably in horses and swine, species in which OC is recognized to have profound health and economic implications. The potential for a translational model of human OC has not been recognized in the existing human literature.

OBJECTIVE

The purpose of this review is to highlight the similarities in signalment, predilection sites and clinical presentation of naturally-occurring OC in humans and animals and to propose a common pathogenesis for this condition across species.

STUDY DESIGN

Review.

METHODS

The published human and veterinary literature for the various manifestations of OC was reviewed. Peer-reviewed original scientific articles and species-specific review articles accessible in PubMed (US National Library of Medicine) were eligible for inclusion.

RESULTS

A broad range of similarities exists between OC affecting humans and animals, including predilection sites, clinical presentation, radiographic/MRI changes, and histological appearance of the end-stage lesion, suggesting a shared pathogenesis across species.

CONCLUSION

This proposed shared pathogenesis for OC between species implies that naturally-occurring and surgically-induced models of OC in animals may be useful in determining risk factors and for testing new diagnostic and therapeutic interventions that can be used in humans.

Operative Fixation of Chondral Loose Bodies in Osteochondritis Dissecans in the Knee: A Report of 5 Cases

BACKGROUND

Osteochondritis dissecans (OCD) can progress to loose body formation, with or without subchondral bone attachment to the lesion. The efficacy of internal fixation of chondral loose bodies has not been determined.

HYPOTHESIS

Operative fixation of cartilaginous loose bodies would result in (1) healed OCD at second-look arthroscopy, (2) restored cartilage appearance on magnetic resonance imaging (MRI), and (3) nearly normal knee function, as determined by patient-reported outcome scores.

STUDY DESIGN

Retrospective case series; Level of evidence, 4.

METHODS

Five patients who underwent cartilaginous loose body fixation were identified. Lesions were located on the lateral trochlea (n = 2) and medial femoral condyle (n = 3) (mean size, 2.5 cm(2)). Loose bodies were reattached with compression screws through mini-arthrotomy or arthroscopy. Patients were nonweightbearing for 12 weeks postoperatively. After 12 weeks, screws were removed arthroscopically, and OCD stability was evaluated. Three patients underwent MRI to determine articular cartilage status. Images were evaluated using the magnetic resonance observation of cartilage repair tissue (MOCART) score. Patients were interviewed and completed the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire.

RESULTS

Four patients had stable lesions at 12 weeks after surgery. One patient had slight motion to one-third of the lesion and stability to the remaining two-thirds. Three patients underwent an MRI. The mean time from surgery to MRI was 3.1 years. Mean MOCART score was 72.0 ± 10.4. One patient required repeat arthroscopy 1 year after initial fixation for debridement and arthroscopic drilling of an incompletely healed area of the lesion. Four patients completed the KOOS questionnaire. The mean time to KOOS completion was 4.6 years. Mean KOOS subscales for knee pain (91.0 ± 8.9), knee symptoms (83.0 ± 7.9), and function in activities of daily living (91.9 ± 10.6) were similar to published age-matched controls; however, scores for sports and recreation function (70.0 ± 17.8) and knee-related quality of life (67.2 ± 12.9) were lower.

CONCLUSION

Operative fixation of chondral loose bodies, without macroscopically visible subchondral bone attachment, resulted in lesion stability at second-look arthroscopy. At final follow-up, patients had no substantial pain and normal function in activities of daily life compared with controls; however, knee-related quality of life and sport and recreation function were reduced, and 1 patient required reoperation for an unhealed portion of the lesion.

A review of knowledge in osteochondritis dissecans: 123 years of minimal evolution from König to the ROCK study group

BACKGROUND

Osteochondritis dissecans (OCD) was first described to provide an explanation for the nontraumatic development of loose bodies within a joint. Despite many reports on the subject, there remains no clear understanding of the etiology, natural history, or treatment.

QUESTIONS/PURPOSES

This review was undertaken to delineate (1) the etiology of OCD; (2) the presentation and locations; (3) the most appropriate imaging modalities; and (4) the most effective treatment strategies.

METHODS

We reviewed the English literature using a database compiled from a Medline search for "osteochondritis dissecans". We identified 1716 publications, 1246 of which were in English. After exclusions, we reviewed 748 articles and of these cited 85. The observations of each study were then synthesized into this report.

RESULTS

There appears to be no consensus concerning the etiology of OCD lesions. The presentations and locations are variable, but the knee, ankle, and elbow are most commonly involved. Although plain film assessment is important in OCD, there appears to be a trend toward the use of MRI, but the preferred sequences are in evolution. We found no consensus on the treatment of these lesions, related in part to the lack of agreement of methods for assessing outcomes.

CONCLUSIONS

Despite more than a century of study, we have made little advancement in our understanding of OCD. A study group has been formed to address this issue and actively seeks to answer these unknown issues regarding OCD.

Osteochondritis dissecans knee histology studies have variable findings and theories of etiology

BACKGROUND

Although many etiological theories have been proposed for osteochondritis dissecans (OCD), its etiology remains unclear. Histological analysis of the articular cartilage and subchondral bone tissues of OCD lesions can provide useful information about the cellular changes and progression of OCD. Previous research is predominantly comprised of retrospective clinical studies from which limited conclusions can be drawn.

QUESTIONS/PURPOSES

The purposes of this study were threefold: (1) Is osteonecrosis a consistent finding in OCD biopsy specimens? (2) Is normal articular cartilage a consistent finding in OCD biopsy specimens? (3) Do histological studies propose an etiology for OCD based on the tissue findings?

METHODS

We searched the PubMed, Embase, and CINAHL databases for studies that conducted histological analyses of OCD lesions of the knee and identified 1560 articles. Of these, 11 met our inclusion criteria: a study of OCD lesions about the knee, published in the English language, and performed a histological analysis of subchondral bone and articular cartilage. These 11 studies were assessed for an etiology proposed in the study based on the study findings.

RESULTS

Seven of 11 studies reported subchondral bone necrosis. Four studies reported normal articular cartilage, two studies reported degenerated or irregular articular cartilage, and five studies found a combination of normal and degenerated or irregular articular cartilage. Five studies proposed trauma or repetitive stress and two studies proposed poor blood supply as possible etiologies.

CONCLUSIONS

We found limited research on histological analysis of OCD lesions of the knee. Future studies with consistent methodology are necessary to draw major conclusions about the histology and progression of OCD lesions. Inconsistent histologic findings have resulted in a lack of consensus regarding the presence of osteonecrosis, whether the necrosis is primary or secondary, the association of cartilage degeneration, and the etiology of OCD. Such studies could use a standardized grading system to allow better comparison of findings.

Drilling juvenile osteochondritis dissecans: retro- or transarticular?

BACKGROUND

Early diagnosis and successful treatment of juvenile osteochondritis dissecans (JOCD) is essential in preventing articular degeneration at a young age. Surgical treatment of stable JOCD lesions failing nonoperative treatment involves retroarticular or transarticular drilling to induce revascularization and healing. Multiple case series report high healing rates and infrequent complications for both retroarticular and transarticular drilling modalities; however, it is unclear from these individual reports whether one mode of drilling provides higher healing rates.

QUESTIONS/PURPOSES

We asked whether transarticular or retroarticular drilling of stable JOCD lesions results in differing patient-oriented outcomes, rates of radiographic healing, time to radiographic healing, and complication rates.

METHODS

We systematically reviewed the short-term clinical outcomes of retroarticular and transarticular drilling of stable OCD lesions. PubMed and additional sources identified 65 studies; 12 studies met inclusion criteria.

RESULTS

Heterogeneity and quality of studies limited review to qualitative analysis. No clear differences were seen in patient-oriented outcomes after treatment with either drilling modality. Radiographic healing for JOCD lesions drilled retroarticularly occurred in 96 of 111 (86%) lesions in an average of 5.6 months. Transarticular drilling of JOCD lesions resulted in 86 of 94 (91%) lesions healing by radiography in an average of 4.5 months. No complications were reported for either drilling modality.

CONCLUSIONS

Retroarticular and transarticular drilling of stable lesions results in comparable short-term patient-oriented outcomes and radiographic healing. Further high-quality comparative studies are required to adequately compare drilling modalities, clearly define radiographic healing, and patient-oriented outcomes after nonoperative treatment.

Can fresh osteochondral allografts restore function in juveniles with osteochondritis dissecans of the knee?

BACKGROUND

Failure of initial treatment for juvenile osteochondritis dissecans (OCD) may require further surgical intervention, including microfracture, autograft chondrocyte implantation, osteochondral autografting, and fresh osteochondral allografting. Although allografts and autografts will restore function in most adults, it is unclear whether fresh osteochondral allograft transplantations similarly restore function in skeletally immature patients who failed conventional treatment.

QUESTIONS/PURPOSES

Therefore, we determined function in (1) daily activity; (2) sports participation; and (3) healing (by imaging) in children with juvenile OCD who failed conventional therapy and underwent fresh osteochondral allograft transplantation.

METHODS

We retrospectively reviewed 11 children with OCD of the knee treated with a fresh stored osteochondral allograft between 2004 and 2009 (six males and five females). The average age of the children at the time of their allograft surgery was 15.2 years (range, 13-20 years). The clinical assessments included physical examination, radiography, MRI, and a modified Merle D'Aubigné-Postel score. The size of the allograft was an average of 5.11 cm(2). The minimum followup was 12 months (average, 24 months; range, 12-41 months).

RESULTS

All patients had returned to activities of daily living without difficulties at 6 months and returned to full sports activities between 9 and 12 months after surgery. The modified Merle D'Aubigné-Postel score improved from an average of 12.7 preoperatively to 16.3 at 24 months postoperatively. Followup radiographs at 2 years showed full graft incorporation and no demarcation between the host and graft bone.

CONCLUSIONS

Our observations suggested fresh osteochondral allografts restored short-term function in patients with juvenile OCD who failed standard treatments.

LEVEL OF EVIDENCE

Level IV, case series. See Guidelines for Authors for a complete description of levels of evidence.

Conservative treatment for juvenile osteochondritis dissecans of the talus

PURPOSE

To assess outcome of 6 juvenile patients with osteochondritis dissecans (OCD) of the ankle treated conservatively.

METHODS

Records of 4 males and one female aged 10.8 to 14.1 (mean, 12.3) years who underwent cast immobilisation and/or restriction of physical activities for OCD of the talus (4 on the left and 2 on the right) were reviewed. OCD lesions were graded using the Berndt and Harty classification. Functional outcome was assessed using the ankle-hindfoot score of the American Orthopaedic Foot and Ankle Society. Clinical and radiographic outcomes were assessed according to the Higuera classification.

RESULTS

The mean follow-up period was 30.5 (range, 11-63) months. The mean ankle-hindfoot score was 90 (range, 86-100). Radiological resolution of OCD was noted in 2 ankles, although all ankles showed some degree of healing. All patients had resolution of pain after a mean of 7 (range, 3-12) months. According to the Higuera classification, clinical outcome was excellent in one and good in 5 ankles, whereas radiological outcome was excellent in 2, good in 2, and fair in 2 ankles. In one patient, the OCD of the right posteromedial talar dome resolved spontaneously.

CONCLUSION

Almost all patients achieved good functional outcome after conservative management, regardless of the presence of radiological evidence of healing. Surgery should only be performed if the OCD is unstable.

Juvenile osteochondritis dissecans of the knee: predictors of lesion stability

BACKGROUND

Recent data suggest magnetic resonance imaging (MRI) is the best method to analyze the status of the cartilage and subchondral bone in patients with juvenile osteochondritis dissecans (JOCD).

METHODS

MRI analysis of 122 knees and 132 JOCD lesions in 109 patients who underwent arthroscopic treatment for osteochondritis dissecans lesions of the knee between March 2003 and January 2011.

RESULTS

Agreement between MRI and arthroscopic grading was 62.1%. MRI sensitivity was 92% and specificity was 55%. Positive predictive value of MRI was 33% and negative predictive value of MRI was 97%. In a multivariable logistic regression model, the odds of a unstable lesion on the lateral femoral condyle nonweight-bearing location were 15.7 times greater than the odds of an unstable lesion on the medial femoral condyle weight-bearing area (95% confidence interval: 2.6-95.7, P=0.003.) The odds of the lateral femoral condyle weight-bearing lesion having an unstable grade were also greater than for a medial femoral condyle weight-bearing lesion, but the results were not statistically significant (odds ratio, 1.70, P=0.349).

CONCLUSIONS

A high T2 signal retrograde to the lesion may commonly appear with an early, stable arthroscopic grade lesion. MRI continues to be reliably sensitive to JOCD lesions and a good predictor of low-grade, stable lesions. However, MRI predictability of high-grade, unstable JOCD lesions is less reliable. Lesions in atypical locations, such as the nonweight-bearing surface of the lateral femoral condyle, more commonly present as higher, arthroscopic grade lesions.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Long-term results of arthroscopic excision of unstable osteochondral lesions of the lateral femoral condyle

The purpose of this study was to evaluate the long-term functional and radiological outcomes of arthroscopic removal of unstable osteochondral lesions with subchondral drilling in the lateral femoral condyle. We reviewed the outcome of 23 patients (28 knees) with stage III or IV osteochondritis dissecans lesions of the lateral femoral condyle at a mean follow-up of 14 years (10 to 19). The functional clinical outcomes were assessed using the Lysholm score, which improved from a mean of 38.1 (sd 3.5) pre-operatively to a mean of 87.3 (sd 5.4) at the most recent review (p = 0.034), and the Tegner activity score, which improved from a pre-operative median of 2 (0 to 3) to a median of 5 (3 to 7) at final follow-up (p = 0.021). The radiological degenerative changes were evaluated according to Tapper and Hoover’s classification and when compared with the pre-operative findings, one knee had grade 1, 22 knees had grade 2 and five knees had grade 3 degenerative changes. The overall outcomes were assessed using Hughston’s rating scale, where 19 knees were rated as good, four as fair and five as poor.

We found radiological evidence of degenerative changes in the third or fourth decade of life at a mean of 14 years after arthroscopic excision of the loose body and subchondral drilling for an unstable osteochondral lesion of the lateral femoral condyle. Clinical and functional results were more satisfactory.

Bioabsorbable fixation of unstable osteochondritis dissecans lesions

BACKGROUND

Osteochondritis dissecans lesions of the knee in adult patients frequently require surgical intervention. However, the ideal method of osteochondral fragment fixation remains uncertain.

PURPOSE

This study was undertaken to determine the clinical, functional, and radiographic outcomes of bioabsorbable fixation for unstable osteochondritis dissecans lesions involving the femoral condyles of the knee in skeletally mature patients.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Skeletally mature patients with an unstable osteochondritis dissecans lesion of the femoral condyle (Ewing and Voto stages II-IV) treated with bioabsorbable internal fixation and minimum 1-year follow-up were included in this retrospective study cohort. Pre- and postoperative radiographs were reviewed and postoperative Lysholm and International Knee Documentation Committee (IKDC) scores were documented.

RESULTS

A total of 21 knees in 21 patients satisfied the inclusion criteria, and 3 patients were lost to follow-up. The remaining 18 patients were evaluated at a mean of 59 months after surgery (range, 12-154 months). The 14 male and 4 female patients had a mean age of 19 years at the time of surgery (range, 14-39 years). Ewing and Voto classification included 8 stage II lesions, 9 stage III lesions, and 1 stage IV lesion. Fragment fixation methods included bioabsorbable nails (11), pins (3), darts (2), screws (1), and combined screws and darts (1). Mean postoperative Lysholm and IKDC scores were 85 and 82, respectively. Fragment union occurred in 12 knees (67%); the remaining 6 knees (33%) required removal of the loose fragment. Of the 11 patients treated with bioabsorbable nails, 2 (18%) required reoperation for nail back-out.

CONCLUSION

The authors recommend caution when using bioabsorbable fixation for osteochondritis dissecans lesions in skeletally mature patients because of the low rate of clinical healing and high complication rate. Failure with unthreaded fixation devices may be caused by inadequate compression and not necessarily be related to bioabsorbability.

Does operative fixation of an osteochondritis dissecans loose body result in healing and long-term maintenance of knee function?

BACKGROUND

Osteochondritis dissecans (OCD) can progress to loose body formation, resulting in a grade IV defect. The decision to fix versus excise the loose body is controversial. Published operative fixation outcomes are small case series with short follow-up.

HYPOTHESIS

Operative fixation (ORIF) of the loose body into the grade IV defect will heal and approximate "normal" knee function at long-term follow-up.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Twelve patients were identified who underwent ORIF of a knee OCD loose body into the grade IV osteochondral defects ranging in size from 2.0 to 8.0 cm(2) (mean, 3.5 cm(2)). After 12 weeks, hardware was removed, and healing was assessed. Long-term outcomes were assessed with a Knee injury and Osteoarthritis Outcome Score (KOOS) and a Marx activity score.

RESULTS

Arthroscopy for screw removal revealed stable healing in 92% (11 of 12) of patients. No patients required subsequent surgery for a loose body. At an average of 9.2 years' follow-up (range, 3.8-15.8 years), 83% (10 of 12) of patients completed the KOOS. The KOOS subscale scores for pain (mean, 87.8; range, 67-100), other symptoms (mean, 81.8; range, 61-96), function in activities of daily living (mean, 93.1; range, 72-100), and sports and recreation function (mean, 74.0; range, 40-100) were not significantly lower than those of published age-matched controls. However the KOOS subscale score for knee-related quality of life (mean, 61.9; range, 31-88) was significantly lower (P = .003).

CONCLUSION

Operative fixation of grade IV OCD loose bodies results in stable fixation. At an average 9 years after surgery, patients did not have symptoms of osteoarthritis pain and had normal function in activities of daily life. However, patients reported significantly lower knee-related quality of life. Operative fixation of OCD loose bodies is a better alternative to lesion excision.

Extraarticular drilling for stable osteochondritis dissecans in the skeletally immature knee

BACKGROUND

Osteochondritis dissecans of the knee is an increasingly frequent diagnosis in the skeletally immature, in whom it is known as juvenile osteochondritis dissecans (JOCD). Although many stable lesions heal with nonoperative treatment, surgical management may be necessary when this treatment fails. Our objective is to determine if extraarticular drilling is an effective treatment for JOCD.

METHODS

Patients who underwent extraarticular drilling for stable JOCD of the knee at the authors' institution between 1998 and 2006 were identified. Demographic information, the location of the lesion, duration of symptoms before surgery, occurrence of complications, postoperative course, and length of follow-up were documented from each patient's medical record. The outcome measures were normal examination, radiographic evidence of healing, and full return to activity.

RESULTS

Fifteen skeletally immature patients (16 knees) were identified. There were 8 boys and 7 girls, with 8 right and 8 left knees. One girl had bilateral lesions. The lesions were located in the medial femoral condyle in 12 knees and in the lateral femoral condyle in 4 knees. The average duration of symptoms before surgery was 21 months (range, 3 months-9 years). The average age at the time of surgery was 12 years, 4 months (range, 9-15 years). There were no intraoperative or postoperative complications. The average follow-up was 21 months (range, 8-38 months). Three of the 15 patients were lost to follow-up. In the remaining 12 patients, 12 knees had excellent outcomes with full return to activities, normal examinations, and radiographic evidence of healing. One knee had fair results. On average, these criteria were met at 8.5 months after surgery.

CONCLUSIONS

When nonoperative management of stable JOCD fails, arthroscopic extraarticular drilling is an effective treatment to protect the articular surface and promote bone healing.

LEVELS OF EVIDENCE

Level IV case series.

The healing potential of stable juvenile osteochondritis dissecans knee lesions

BACKGROUND

The purpose of the present study was to determine if patient age, lesion size, lesion location, presenting knee symptoms, and sex predict the healing status after six months of a standard protocol of nonoperative treatment for stable juvenile osteochondritis dissecans of the knee.

METHODS

Forty-two skeletally immature patients (forty-seven knees) who presented with a stable osteochondritis dissecans lesion were included in the present study. All patients were managed with temporary immobilization followed by knee bracing and activity restriction. The primary outcome measure of progressive lesion reossification was determined from serial radiographs every six weeks, for up to six months of nonoperative treatment. A multivariable logistic regression model was used to determine potential predictors of healing status from the listed independent variables.

RESULTS

After six months of nonoperative treatment, sixteen (34%) of forty-seven stable lesions had failed to progress toward healing. The mean surface area (and standard deviation) of the lesions that showed progression toward healing (208.7 +/- 135.4 mm(2)) was significantly smaller than that of the lesions that failed to show progression toward healing (288.0 +/- 102.6 mm(2)) (p = 0.05). A logistic regression model that included patient age, normalized lesion size (relative to the femoral condyle), and presenting symptoms (giving-way, swelling, locking, or clicking) was predictive of healing status. Age was not a significant contributor to the predictive model (p = 0.25).

CONCLUSIONS

In two-thirds of immature patients, six months of nonoperative treatment that includes activity modification and immobilization results in progressive healing of stable osteochondritis dissecans lesions. Lesions with an increased size and associated swelling and/or mechanical symptoms at presentation are less likely to heal.

[Treatment of osteochondritis dissecans of the knee joint]

Osteochondritis dissecans (OD) is a lesion of the subchondral bone which can result in sequestration of the osteochondral lesion. It is categorized into 4 stages, and juvenile and adult forms depending on the distal femoral physis maturity. Prognosis and treatment depends on age and stage. Prognosis is favorable in stable lesions (stage I and II) at typical location (medial femoral condyle) in a child with open physes. Therefore non-operative treatment is indicated. If there is no response to non-operative treatment drilling to create channels for potential revascularization can be done. In unstable lesions (stage III and IV) operative treatment is necessary. Long-term results after excision of the fragment with or without drilling of the defect site are poor. Therefore refixation of an intact osteochondral fragment or biologic reconstruction should be tried.

Retroarticular drilling and bone grafting of juvenile osteochondritis dissecans of the knee

We present an effective technique for retroarticular drilling and bone grafting of juvenile osteochondritis dissecans (OCD). A radiolucent bolster is used to flex the knee at 45 degrees, allowing adequate C-arm visualization. A 2-cm incision is made over the iliac spine, and soft tissue is dissected with the use of electrocautery. A 3.5-mm Steinmann pin is driven approximately 5 cm into the iliac crest. With a mallet, the 3.5-mm-long drill sleeve from the Synthes External Fixator Set (Part #395.913; Synthes, Paoli, PA) is tamped over and 1 cm past the guide pin, while cores of autograft cancellous bone are harvested. The same Steinmann pin is inserted over the corresponding aspect of the knee. The Steinmann pin is advanced to approximately 1 cm above the lesion, and the drill guide is once again tapped over the pin. With use of the C-arm, the pin is removed, and a 3.5-mm bit is used to drill the remaining distance into the lesion. The graft is tamped through the drill guide and into position with the reverse end of the bit. This technique may be repeated according to the size of the lesion. Major advantages of this technique include the ease of harvest/transfer of autograft, readily available instrumentation to perform the procedure, and the ability to avoid violation of stable articular cartilage.

Review for the generalist: evaluation of anterior knee pain

Anterior knee pain is common in children and adolescents. Evaluation and management is challenging and requires a thorough history and physical exam, and understanding of the pediatric skeleton. This article will review common causes of chronic anterior knee pain in the pediatric population with a focus on patellofemoral pain.

Osteochondritis dissecans of the elbow: Histopathological assessment of the articular cartilage and subchondral bone with emphasis on their damage and repair

Osteochondritis dissecans (OCD) of the elbow is a localized injury of the articular cartilage and subchondral bone that is commonly seen in the young athlete. In the present study, the extent of damage and repair on the articular cartilage and subchondral bone was examined histologically using specimens of 25 osteochondral cylinders and seven loose bodies obtained from 25 young athletes who had undergone osteochondral autograft surgery. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) assays for detecting apoptotic cells and immunohistochemistry of matrix metalloproteinases (MMP) were performed on the osteochondral cylinder specimens. The histological findings of the OCD of the elbow showed that the articular cartilage exhibited degenerative change, mimicking osteoarthritis, and was markedly damaged as the lesion progressed. TUNEL-positive cells and MMP-3- and -13-expressing cells were distributed in the degenerative articular cartilage and reparative fibrocartilage tissue. Separation occurred at either the deep articular cartilage or the subchondral bone, with the former being dominant in the early OCD lesions. The present results suggest that the primary pathological changes in OCD of the elbow were due to damage of articular cartilage induced by repeated stress following degenerative and reparative process of articular cartilage and subchondral fracturing, and separation subsequently occurred on the cartilage and developed onto the subchondral bone in its advanced stages.

Musculoskeletal injuries in sports

A large number of adolescents participate in various sports. Not withstanding the methodologic problems with epidemiologic data, a large percentage of athletes sustain musculoskeletal injuries. In most instances, the athlete first presents to his or her primary care physician, who must perform the initial assessment and decide on further management. Many injuries can be managed by the primary care physician. It is important to recognize the unique characteristics of adolescent growth and development that have implications for the diagnosis and management of musculoskeletal injuries.