Review Question - QID 219442

Arthroscopic debridement and drilling of the capitellar lesion is the best treatment choice for a small (<1 cm^2), unstable OCD with intact cartilage.

Capitellar OCDs are relatively uncommon but are typically seen in overhead throwers or gymnasts in the 12-17 year old range. Males are disproportionately affected. They often present insidiously with pain and eventually progress to having a loss of motion and sensations of catching/locking. Radiographs can confirm suspicion and MRI has been shown to be best at predicting stability of the OCD, although not perfect. Also important to recognize on the MRI are the size and location of the lesion as well as the status of the overlying cartilage. If the OCD is relatively small and stable on the MRI with no mechanical symptoms, nonoperative management is reasonable. If there is concern for instability of the lesion or mechanical symptoms on exam, consideration should be given to operative intervention. Arthroscopic debridement and drilling is the most common treatment in cases where the overlying cartilage is intact and the lesion is <1 cm^2. In larger lesions or those located more eccentrically on the capitellum, ostechondral autograft/allograft may be a better choice to address the OCD.

Kessler et al. looked at the demographics and epidemiology of elbow OCDs among children and adolescents at their health system between 2007-2011. They noted 98% of the lesion occurred in the capitellum and the majority of cases were seen in those aged 12-19 years. Among this population, males were 6.8x more likely to have an elbow OCD.

Pu et al. performed a systematic review looking at the radiographic evaluation of capitellar OCDs to determine the agreement of different classifications with intraoperative findings. They noted that MRI-based classification systems had better predictive findings relative to their intraoperative presentation, although no one system was completely effective. They concluded that a combination of radiographs, MRI, and CT are most accurate in determining OCD stability although they do not necessarily advocate CT in all patients of this age group given the radiation exposure.

Ruchelsman et al. published a review of capitellar OCDs, noting it is most commonly seen in gymnasts and overhead athletes and most likely results from microtrauma and vascular changes. MRI is helpful to understand the lesion and size, location, and grade of the lesion all contribute to treatment decision making. Surgery is typically indicated for unstable lesions and most commonly involves arthroscopic marrow stimulation

Incorrect Answers:
Answer 1: Given the patient's mechanical symptoms and lesion instability on MRI, he would be indicated for surgical management.
Answer 3: With an intact cartilage cap and no loose bodies, fragment removal would be avoided if at all possible in this patient. Drilling of the capitellum to stimulate healing of the unstable lesion would be preferred in an unstable lesion of this size.
Answer 4: Osteochondral autograft transplantation (OATS) can be performed with capitellar lesion and the graft is normally taken from the lateral trochlea of the ipsilateral knee. That said, there is no indication for osteochondral transfer in this patient at this time given the size and cartilage status of the lesion noted on MRI.
Answer 5: Osteochondral allografts may also be useful in these patients and are typically implanted through an open posterolateral elbow approach. Similar to OATS in this patient, an allograft would not currently be indicated.