Chondral Lesion of the Capitellum Humeri Accompanying a Radial Head Fracture: A Case Report

In this case report we present a case of a full thickness chondral lesion of the anterior-distal surface of the capitellum humeri, accompanying an intraarticular radial head fracture. The importance of this case is the resemblance of the chondral injury to a Lorenz-Kocher lesion of the humerus and atypical displacement of chondral fragments. A 32-year-old man was admitted to the emergency room after a fall on his right upper extremity. X-ray and Computed Tomography (CT) scan of the elbow revealed a minimally displaced radial head fracture (Mason type 2), with a 4 mm step (depression) at the joint surface. During the operation, at the anterior surface of the distal humerus, a full thickness chondral lesion was encountered.After removal of chondral fragments from the fractured radial head surface, it was seen that these fragments were of capitellar origin. Following radial head fixation, early active assistive motion was started. At the 6 month visit, the patient was painfree with full participation in activities of daily livingwith a DASH score of 12.5. This injury is important due to demonstration of such an extensile injury in spite of benign looking radiology. Although radial head fractures were described, these type of occult injuries may be responsible for unexplainable and unfavorable outcomes following low energy radial head fractures treated conservatively.

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[1] Zwingmann J, Welzel M, Dovi-Akue D, Schmal H, Südkamp NP, Strohm PC. Clinical results after different operative treatment methods of radial head and neck fractures. A systematic review and meta-analysis of clinical outcome. Injury. 2013; 44(11):1540- 50.

[2] Duguet B, Le Saout J. Fractures du capitellum chez l'enfant. [Capitellum fractures of children (author's transl)]. Chir Pediatr. 1980; 21(5):331-3. [Article in French].

[3] Hope PG, Williamson DM, Coates CJ, Cole WG. Biodegradable pin fi•xation of elbow fractures in children. J Bone Joint Surg Br. 1991; 73(6):965-8.

[4] Cottalorda J , Bourelle S. The often missed Kocher-Lorenz elbow fracture. Orthop Traumatol Surg Res. 2009; 95(7):547- 50.

[5] Nalbantoglu U, Gereli A, Kocaoglu B, Aktas S, Turkmen M. Capitellar cartilage injuries concomitant with radial head fractures. J Hand Surg Am. 2008; 33(9):1602-7.

[6] Caputo AE, Burton KJ, Cohen MS, King GJ. Articular cartilage injuries of the capitellum interposed in radial head fractures: a report of ten cases. J Shoulder Elbow Surg. 2006; 15(6):716-20.

[7] Duckworth AD, Watson BS, Will EM, Petrisor BA, Walmsley PJ, Court-Brown CM, et al. Radial head and neck fractures: functional results and predictors of outcome. J Trauma. 2011 Sep;71(3):643-8.