Osteochondritis dissecans (OCD) in the skeletally

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1 ORIGINAL ARTICLE 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 Joseph L. Yellin, BA,*w Itai Gans, MD,z James L. Carey, MD, MPH,y Kevin G. Shea, MD,8 and Theodore J. Ganley, MD*w 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 s 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 s 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 s with drilling in a retroarticular or transarticular manner. Preferred treatment for unstable, salvageable s was screw From the *Division of Orthopaedic Surgery, The Children s Hospital of Philadelphia; wperelman School of Medicine at the University of Pennsylvania; ydepartment of Orthopaedic Surgery, University of Pennsylvania Health System, Philadelphia, PA; zdepartment of Orthopaedic Surgery, Johns Hopkins Medicine, Baltimore, MD; and 8Department of Orthopedics, St Luke s Clinics, Boise, ID. The authors have no financial disclosures. The authors declare no conflicts of interest. Reprints: Theodore J. Ganley, MD, Division of Orthopaedic Surgery, The Children s Hospital of Philadelphia, 34th Street and Civic Center Blvd, Richard D. Wood Ambulatory Care Building, Second Floor, Philadelphia, PA ganley@ .chop.edu. Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal s Website, Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved. fixation using bioabsorble materials or metal with variable pitch with no bone graft. The majority of respondents would treat unstable, unsalvageable OCD s 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 s in the skeletally immature, whereas individual techniques of achieving these principles may vary. Members endorse drilling for stable intact s; fixation for unstable, salvageable s; and defect fill for unsalvageable s. 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. Key Words: osteochondritis dissecans, OCD, pediatrics, skeletally immature, POSNA, Pediatric Orthopaedic Society of North America (J Pediatr Orthop 2015;00: ) Osteochondritis dissecans (OCD) in the skeletally immature is a common and increasingly prevalent cause of knee pain and dysfunction in the adolescent patient population. 1 OCD is defined as a focal idiopathic alteration of subchondral bone with risk for instability and disruption of adjacent articular cartilage that may result in premature osteoarthritis. 2 While the etiology of the disease process remains unknown, several factors have been implicated including trauma, overuse and repetitive microtrauma, vascular insufficiency, and genetic predisposition. 3 5 Adolescent patients with OCD characteristically present with localized knee pain, joint stiffness, and occasional locking that may occur following a long history of playing competitive and/or recreational sports. 6 Individuals affected typically reduce activity and decrease sports participation to limit pain. 7 However, without appropriate treatment, failure of OCD s to heal fully may result in an increased risk for developing premature osteoarthritis, a physically painful and financially burdening sequela Therefore, the aim of treatment is J Pediatr Orthop Volume 00, Number 00,

2 Yellin et al J Pediatr Orthop Volume 00, Number 00, 2015 pain relief, improved knee function, and potential alteration of the degenerative joint process. Treatment for OCD in the skeletally immature includes nonoperative and surgical management. Stable s with radiographic evidence of an intact articular surface are deemed to have an acceptable probability of healing and are frequently initially managed nonoperatively. First-line nonoperative treatment includes trials of non weight-bearing, casting, and physical therapy for a period of 3 to 6 months. Stable s that fail to heal with nonoperative measures that are confirmed to be intact arthroscopically are typically treated with 1 of 2 drilling techniques, transarticular or retroarticular. 12 The 2 techniques create channels in the subchondral bone, which allow for revascularization and bony union of the osteochondral fragment. 13 In a recent systematic review performed by Gunton et al, 13 both techniques have been shown to be comparably effective across a variety of short-term patient-oriented outcomes (including pain and patient function scores) and in producing radiographic healing. Lesions determined to be unstable but salvageable on arthroscopic evaluation generally undergo various means of fixation. Unstable and unsalvageable s generally require cartilage repair or restoration, achieved through varying types of surgical intervention. A sizeable body of literature exists detailing the principles and characteristics of OCD of the knee in the skeletally immature who require surgery to heal. 6,14,15 However, as alluded to previously, there are a large number of techniques and surgical procedures that orthopaedic surgeons can utilize to achieve similar results in the operative treatment of different types of OCD s of the knee. Because of a scarcity of prospective highquality clinical studies, no universal consensus exists to guide clinicians on therapeutic decision making, including nonoperative or operative intervention, timing of treatment, or surgical method. 16 The purpose of this study is to determine current trends in surgical treatment for OCD s in the skeletally immature patients who have failed nonoperative management by surveying a large cohort of orthopaedic surgeons. METHODS After obtaining approval from the Institutional Review Board and the Pediatric Orthopaedic Society of North America (POSNA), an electronic survey was designed using REDCap to capture surgeon treatment preferences for OCD s in the skeletally immature. It was distributed to members of POSNA using REDCap survey software through . Follow-up s were sent 2 and 6 weeks after the initial invitation. The survey remained open for a total period of 8 weeks. Surgeons names were not collected. Participants were not compensated for their responses. Of note, while the principle investigator is a member of POSNA, this study was not conducted by a POSNA committee. The survey was divided into multiple sections. Section 1 contained 4 questions about demographics and clinical experience. Specifically, the survey inquired about the stage of training and years of orthopaedic experience, practice environment (ie, academic center, private practice, or a combination), frequency of treating patients with OCD, and the skeletal age of the patients treated with OCD (ranging from all skeletally immature to all skeletally mature). Section 2 contained 3 clinical vignettes corresponding to the different OCD s common to skeletally immature patients: clearly intact and stable after failing nonoperative treatment, unstable and salvageable, and unstable and unsalvageable. Each vignette consisted of a brief pertinent history and physical exam accompanied by imaging data from radiographs, magnetic resonance imaging (MRI), and arthroscopy. Responses to the vignettes were multiple-choice based upon the most common treatment methods for each scenario. Patient information was not accessed when constructing the history and physical exam portion of the vignettes. No actual patient data were gathered during this study. Once the survey closed, data were collected and analyzed at The Children s Hospital of Philadelphia in the Division of Orthopaedic Surgery and the Sports Medicine and Performance Center. Microsoft Excel 2011 was used to summarize the responses to all survey questions. RESULTS A total of 129 members (B11%) of the POSNA delegation completed the pediatric section of the dis- TABLE 1. Survey Respondents Demographic Data Respondents Survey Question Answer Choice [n (%)] Level of training Residency 1 (0.8) Fellowship 2 (1.6) Attending 0-10 y 52 (40.3) Attending y 37 (28.7) Attending 21+ y 37 (28.7) Practice environment Academic institution 70 (54.3) Private practice 32 (24.8) Academic+private 27 (20.9) Patient population treated All skeletally 19 (14.7) immature Mostly skeletally 79 (61.2) immature Mixed 21 (16.3) Mostly skeletally 6 (4.7) mature All skeletally mature 4 (3.1) Frequency of treating OCD Rarely, if ever 3 (2.3) 1 per year 4 (3.1) 1 per 6 mo 30 (23.3) 1 per month 45 (34.9) 1 per week 32 (24.8) Almost daily 15 (11.6) Total respondents to pediatric survey section 129 Osteochondritis dissecans (OCD) in the skeletally immature survey respondent demographic data, divided by level of training, surgeon practice environment, patient population treated, and frequency of treating OCD cases in the skeletally immature. 2 Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.

3 J Pediatr Orthop Volume 00, Number 00, 2015 Surgical Management of OCD of the Knee FIGURE 1. Intact, stable OCD 1515 mm seen on radiograph (A), coronal T2 MRI (B), sagittal T1 MRI (C), and arthroscopic view (D). MRI indicates magnetic resonance imaging; OCD, osteochondritis dissecans. tributed survey. Table 1 depicts the demographic information of the respondents. The vast majority of respondents (126, 97.7%) were attending level surgeons; 52 (41.3%) with 0 to 10 years of experience, 37 (29.4%) with 11 to 20 years of experience, and 37 (29.4%) with >20 years in practice. Two fellows and 1 senior resident also completed the survey. Addressing practice environments of the POSNA members who completed the survey, 70 (54.3%) members strictly identified with an academic institution, 32 (24.8%) members were in private practice, and 27 (20.9%) respondents were affiliated with both private and academic practices. Examining the patient population treated by the respondents, 19 (14.7%) identified with treating all skeletally immature patients, 79 (61.2%) treating mostly skeletally immature patients, 6 (4.65%) treating mostly skeletally mature patients, 4 (3.1%) treating all skeletally mature patients, and 21 (16.3%) treating an even distribution of skeletally immature and mature patients. Most respondents (45, 34.9%) treated patients with OCD s about once a month. Fifteen (11.6%) Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved. 3

4 Yellin et al J Pediatr Orthop Volume 00, Number 00, 2015 TABLE 2. Survey Results Survey Question Treatment Preference No. Respondents Respondents (%) Vignette 1: intact, stable Transarticular drilling Retroarticular drilling Fixation with bone grafting Fixation without bone grafting Intercondylar notch drilling No further surgical treatment I prefer not to answer this Vignette 2, part 1: unstable, salvageable Metal variable pitch screws (no head) Metal screws (head) Metal pins (no head) Metal nails (head) Bioabsorbable rods or pins (no head) Bioabsorbable screws Bioabsorbable nails (head) Bone pegs (match sticks) Osteochondral autograft plugs Suture I prefer not to answer this Vignette 2, part 2: unstable, salvageable Vignette 3: unstable, unsalvageable No bone graft Autograft bone from proximal tibia Autograft bone from iliac crest Allograft bone I prefer not to answer this Chondroplasty, cartilage biopsy, and subsequent autologous chondrocyte implantation Microfracture or drilling Chondroplasty and subsequent osteochondral allograft transplantation Osteochondral autograft transfer Chondroplasty No further treatment I prefer not to answer this Osteochondritis dissecans survey results divided by clinical vignette. Raw number of respondents as well as percentages reported per answer choice. respondents treated these patients daily, 32 (24.8%) once a week, 30 (23.3%) once every 6 months, 4 (3.1%) once a year, and 3 (2.3%) treat OCD s rarely, if ever. The survey s first clinical vignette described an intact, stable OCD (Appendix 1, Supplemental Digital Content 1, Abbreviated case: a 14-year-old skeletally immature female soccer player with 1 year of activity-related knee pain. Physical exam elicits point tenderness to the medial femoral condyle and trace effusion. Radiographs and MRI reveal a 1515mmOCDwithnobreachofarticular cartilage (Figs. 1A C). After failure to improve with 6 months of nonoperative therapy, arthroscopy reveals softening at the lateral aspect of the medial femoral condyle without any appreciable mobility of the fragment (Fig. 1D). Survey question: Which procedure do you perform next? Sixty-nine (53.5%) respondents favored retroarticular drilling and 42 (32.6%) selected transarticular drilling. Ten (7.75%) were in favor of fixation without bone grafting. The remaining response breakdown can be found in Table 2. The second clinical vignette described an unstable, but salvageable OCD (Appendix 2, Supplemental Digital Content 2, Abbreviated case: a 14-year-old skeletally immature male football player with 3 months of activity-related knee pain associated with intermittent popping and catching. Physical exam elicits point tenderness to the lateral femoral condyle and small effusion. Radiographs and MRI reveal an OCD at the lateral femoral condyle with articular cartilage breach and subchondral bone cyst formation at the periphery of the (Figs. 2A C), and arthroscopic evaluation notable for a hinged OCD with bone on the undersurface (Fig. 2D). Survey question: After debridement of fibrous tissue at the base and appropriately bleeding viable bone, you choose to fix this with which preferred method of fixation? Forty-one (31.8%) respondents preferred bioabsorbable screws and 30 (23.3%) favored metal variable pitch screws (no head). Twenty-one (16.3%) preferred bioabsorbable nails (head), 17 (13.2%) bioabsorbable 4 Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.

5 J Pediatr Orthop Volume 00, Number 00, 2015 Surgical Management of OCD of the Knee FIGURE 2. Radiograph (A), coronal T2 MRI (B), sagittal T2 MRI (C), and arthroscopic view (D) of an unstable, salvageable OCD at the lateral femoral condyle with articular cartilage breach and subchondral bone cyst formation at the periphery of the. MRI indicates magnetic resonance imaging; OCD, osteochondritis dissecans. rods or pins (no head), and 7 (5.43%) metal screws (head). Refer to Table 2 for the full response breakdown. A follow-up question to this clinical vignette inquired whether the respondent would place bone graft beneath the hinged. Sixty-four (49.6%) preferred no bone graft, 51 favored autograft bone: 42 (32.6%) preferring from the proximal tibia and 9 (6.98%) from the iliac crest. Ten (7.75%) selected allograft bone and 4 (3.10%) chose not to respond. The final vignette assessed the management of an unstable and unsalvageable OCD (Appendix 3, Supplemental Digital Content 3, BPO/A53). Abbreviated case: a 14-year-old skeletally immature male with 2 years of knee pain associated with occasional swelling. Physical exam reveals point tenderness at the medial femoral condyle diffusely and moderate effusion. Radiographs and MRI demonstrate an OCD of medial femoral condyle with a displaced fragment (Figs. 3A C). Arthroscopy is notable for a mm osteochondral defect with several unsalvageable, displaced cartilage fragments and trace undersurface bone (Fig. 3D). Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved. 5

6 Yellin et al J Pediatr Orthop Volume 00, Number 00, 2015 FIGURE 3. Radiograph (A), coronal T2 MRI (B), sagittal T1 MRI (C), and arthroscopic view (D) of an unstable, unsalvageable OCD of medial femoral condyle with a displaced fragment. MRI indicates magnetic resonance imaging; OCD, osteochondritis dissecans. Survey question: After removing all osteochondral loose bodies, which treatment strategy would you advocate? Most respondents (43, 33.3%) selected chondroplasty and subsequent osteochondral allograft transplantation. Thirty-seven (28.7%) advocated for microfracture or drilling, 23 (17.8%) for osteochondral autograft transfer, and 16 (12.4%) for chondroplasty, cartilage biopsy, and subsequent autologous chondrocyte implantation (ACI). The remaining responses can be found in Table 2. For comparative purposes, Table 3 groups survey respondents and their responses by patient type (ranging from surgeons who treat only skeletally immature to surgeons who strictly treat the skeletally mature). Similarly, Table 4 displays respondents responses grouped by surgeon practice environment. DISCUSSION Although several differences in treatment options for various stages of OCD s in the skeletally im- 6 Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.

7 J Pediatr Orthop Volume 00, Number 00, 2015 Surgical Management of OCD of the Knee TABLE 3. Survey Results: Grouped by Patient Population (Skeletal Maturity) Treated by the Respondents Survey Question Vignette 1: intact, stable Treatment Preference All Immature (Total = 19) % Mostly Immature (Total = 79) % Mixed (Total = 21) % Mostly Mature (Total = 6) % All Mature (Total = 4) % Transarticular drilling Retroarticular drilling Fixation with bone grafting Fixation without bone grafting Intercondylar notch drilling No further surgical treatment I prefer not to answer this Vignette 2, part 1: unstable, salvageable Vignette 2, part 2: unstable, salvageable Vignette 3: unstable, unsalvageable Metal variable pitch screws (no head) Metal screws (head) Metal pins (no head) Metal nails (head) Bioabsorbable rods or pins (no head) Bioabsorbable screws Bioabsorbable nails (head) Bone pegs (match sticks) Osteochondral autograft plugs Suture I prefer not to answer this No bone graft Autograft bone from proximal tibia Autograft bone from iliac crest Allograft bone I prefer not to answer this Chondroplasty, cartilage biopsy, and subsequent autologous chondrocyte implantation Microfracture or drilling Chondroplasty and subsequent osteochondral allograft transplantation Osteochondral autograft transfer Chondroplasty No further treatment I prefer not to answer this Osteochondritis dissecans survey results divided by clinical vignette and patient population treated. Values in bold indicate highest percentages/numbers. mature patient exist, some clear patterns have become evident through this survey. In treating intact, stable s, the preponderance of POSNA members completing the survey opts for more conservative treatment measures, including retroarticular and transarticular drilling. Addressing unstable, but salvageable s, the majority of respondents prefer screw fixation (bioabsorbable screws > metal variable pitch screws) to nails, pins, or rods, or sutures. In these same s, more respondents choose not to bone graft than to bone graft (64 vs. 61 respondents). Of those who do, autograft from the proximal tibia is the preferred choice. For the unsalvageable and unstable s, the POSNA survey respondents are in agreement with filling the underlying defect, and the individual techniques vary. Overall, the POSNA membership completing the survey appears to agree on principle in terms of treatment modalities, whereas individual techniques of achieving these principles may vary. Members endorse drilling for stable intact s; fixation for unstable, salvageable s; and defect fill for unsalvageable s. Interestingly, when surgeons were subdivided by the patient population they self-reportedly treat, ranging from only skeletally immature patients through strictly skeletally mature patients (Table 3), no clear treatment preference difference emerged between either of the first 2 clinical vignettes. For the third vignette, describing an unstable and unsalvageable, no clear pattern emerged based on patient population treated, with a mix Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved. 7

8 Yellin et al J Pediatr Orthop Volume 00, Number 00, 2015 TABLE 4. Survey Results: Grouped by Surgeon Practice Environment Survey Question Treatment Preference Academic (Total = 70) % Mixed (Total = 27) % Private Practice (Total = 32) % Vignette 1: intact, stable Transarticular drilling Retroarticular drilling Fixation with bone grafting Fixation without bone grafting Intercondylar notch drilling No further surgical treatment I prefer not to answer this Vignette 2, part 1: unstable, salvageable Metal variable pitch screws (no head) Metal screws (head) Metal pins (no head) Metal nails (head) Bioabsorbable rods or pins (no head) Bioabsorbable screws Bioabsorbable nails (head) Bone pegs (match sticks) Osteochondral autograft plugs Suture I prefer not to answer this Vignette 2, part 2: unstable, salvageable No bone graft Autograft bone from proximal tibia Autograft bone from iliac crest Allograft bone I prefer not to answer this Vignette 3: unstable, unsalvageable Chondroplasty, cartilage biopsy, and subsequent autologous chondrocyte implantation Microfracture or drilling Chondroplasty and subsequent osteochondral allograft transplantation Osteochondral autograft transfer Chondroplasty No further treatment I prefer not to answer this Osteochondritis dissecans survey results divided by clinical vignette and orthopaedic surgeon practice environment. Values in bold indicate highest percentages/numbers. 8 Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.

9 J Pediatr Orthop Volume 00, Number 00, 2015 Surgical Management of OCD of the Knee between chondroplasty and subsequent osteochondral allograft transplantation and microfracture/drilling. Similarly, when the respondents were subdivided based on practice environment (academic vs. private practice), preferred treatment options remained similar for the first 2 clinical vignettes, although a higher percentage of academic surgeons preferred bone grafting in an unstable, salvageable. In treating unstable and unsalvageable s, ACI was preferred more frequently in the purely academic and mixed practice groups (15.7% and 14.8%, respectively), and was rarely seen in the strictly private practice group (3.13%). Perhaps patient referral to academic centers for ACI is accountable for this. Of note, osteochondral autograft transfer was preferred by the simple majority of the private practice surgeons (34.4%) compared with the academic-affiliated surgeons (purely academic, 14.3%; mixed practice, 7.4%). There are several inherent limitations of any survey. Although the survey was distributed to the entire POSNA membership, only the responses from those who completed and returned the survey within the allotted time period (B11% of POSNA membership) were analyzed as representative of the entire group. While this response rate is just above 10%, not all members of POSNA regularly treat OCD and as such, many members who do not regularly treat OCD may not have participated in the survey. In addition, the responses to each question were designed in multiple-choice format, containing the most common treatment modalities. Other, less common surgical procedures might be preferred by some. It is also imperative to note that this study is a report of what POSNA members (who completed the survey) are utilizing in their practices and should not be interpreted as an official statement of support or approval, especially as the effectiveness of each of these procedures in not yet well established. Nonetheless, this survey should prove valuable to the POSNA members and other pediatric orthopaedic surgeons in assessing how their individual practice patterns compare with their peers in POSNA. Furthermore, the information gleaned from this survey can be used in future prospective studies to determine which techniques are most effective for a given indication with the ultimate goal of designing a research-proven nonoperative and operative treatment algorithm for pediatric patients with OCD s of the knee of all types. REFERENCES 1. Wall E, Von Stein D. Juvenile osteochondritis dissecans. Orthop Clin North Am. 2003;34: Edmonds EW, Shea KG. Osteochondritis dissecans: editorial comment. Clin Orthop Relat Res. 2013;471: Mubarak SJ, Carroll NC. Familial osteochondritis dissecans of the knee. Clin Orthop Relat Res. 1979;140: Green WT, Banks HH. Osteochondritis dissecans in children. J Bone Joint Surg Am. 1953;35-A: Crawford DC, Safran MR. Osteochondritis dissecans of the knee. J Am Acad Orthop Surg. 2006;14: Cahill BR. Osteochondritis dissecans of the knee: treatment of juvenile and adult forms. J Am Acad Orthop Surg. 1995;3: Ganley TG, Kocher RL, Flynn MS, et al. Osteochondritis dissecans of the knee. Oper Tech Sports Med. 2006;14: Anderson AF, Pagnani MJ. Osteochondritis dissecans of the femoral condyles. Long-term results of excision of the fragment. Am J Sports Med. 1997;25: Twyman RS, Desai K, Aichroth PM. Osteochondritis dissecans of the knee. A long-term study. J Bone Joint Surg Br. 1991;73: Linden B. Osteochondritis dissecans of the femoral condyles: a longterm follow-up study. J Bone Joint Surg Am. 1977;59: Rosemann T, Laux G, Szecsenyi J. Osteoarthritis: quality of life, comorbidities, medication and health service utilization assessed in a large sample of primary care patients. J Orthop Surg Res. 2007;2: Flynn JM, Kocher MS, Ganley TJ. Osteochondritis dissecans of the knee. J Pediatr Orthop. 2004;24: Gunton MJ, Carey JL, Shaw CR, et al. Drilling juvenile osteochondritis dissecans: retro- or transarticular? Clin Orthop Relat Res. 2013;471: Pill SG, Ganley TJ, Flynn JM, et al. Osteochondritis dessicans of the knee: experiences at The Children s Hospital of Philadelphia and a review of the literature. Univ Pa Orthop J. 2001;14: Schenck RC Jr, Goodnight JM. Osteochondritis dissecans. J Bone Joint Surg Am. 1996;78: Chambers HG, Shea KG, Anderson AF, et al. American Academy of Orthopaedic Surgeons. The diagnosis and treatment of Osteochondritis dissecans. J Bone Joint Surg Am. 2012;94: Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved. 9