[Radial Head Replacement: Management of Elbow and Forearm Instability after Comminuted Radial Head Fractures Associated with Elbow Dislocation]. / Endoprotéza hlavice radia: resení nestability lokte a predloktí pri trístivých zlomeninách hlavice radia spojených s luxací lokte.

PURPOSE OF THE STUDY: This manuscript aims to identify an indication algorithm for the surgical treatment of radial head fractures associated with elbow dislocation. The study compares the mid-term functional outcomes of patients with multifragment radial head fracture treated by resection with the outcomes of patients treated with radial head replacement. MATERIAL AND METHODS: The cohort of 34 patients who sustained a radial head fracture at the mean age of 42.5 years (age range 20-81 years) was broken down into two groups by type of surgery. The EXT group consists of 20 patients with the radial head fracture treated by radial head resection. The END group includes 14 patients treated with the radial head replacement. In all patients, the radial head fracture was associated with elbow dislocation (type IV fracture according to the Mason-Johnston classification). The modified Kocher's surgical approach was used in all patients of both the groups. In the EXT group, resection of the fragmented radial head was performed. In the END group, the ExploR® Modular Radial Head System (Zimmer, Biomet, USA) was used, consisting of a CoCr (cobalt chromium) alloy head and a titanium stem. The pain and the range of motion of the elbow and forearm were evaluated after the completion of the outpatient rehabilitation (the mean follow-up period was 2.4 years). Simultaneously, the elbow joint stability was assessed. Radiographs were taken to detect heterotopic ossifications, proximalization of the radius, and any signs of prosthesis loosening. The frequency of reoperations was followed-up. The MEPS (Mayo Elbow Performance Score) was calculated. RESULTS: In the EXT group, the mean elbow flexion was 117.5° and the mean pronation/supination was 166.9°. In 50% of patients, the MEPS obtained was greater than 90 points, which means an excellent functional outcome. In 1 patient (5%), recurrent elbow dislocation occurred which was the reason for revision surgery (elbow transfixation with the Kirschner wires and medial collateral ligament suture). Revision surgery was also performed in 2 patients (10%) in whom not all the radial head fragments were removed. Moreover, also observed was elbow joint instability (2 patients) and temporary radial nerve paralysis (1 patient). In 1 case discrete proximalization of the radius developed. The patients in the END group showed the mean elbow flexion of 112° and the mean pronation/supination of 135°. The MEPS obtained from 69% of patients was greater than 90 points, which means an excellent outcome. The pain under load was reported by 3 patients (21%). In 5 patients (35%), the X-rays showed radiolucent zone around the stem of the prosthesis. Neither revision surgery, nor prosthesis removal has been performed yet in any patient. No instability, neurological complications or infections have been reported. In both EXT and END group heterotopic ossifications have developed in 4 patients. CONCLUSIONS: Radial head replacement compared to the radial head resection in the management of multifragment fractures associated with elbow dislocations increase the elbow and forearm stability. The group of patients with an implanted radial head prosthesis shows a higher percentage of patients achieving excellent functional outcome than the group of patients with radial head resection. KEY WORDS: radial head, elbow, fracture, dislocation, resection, prosthesis.

[Our Initial Experience with Radial Head Replacement]. / První zkusenosti s náhradou hlavice radia.

PURPOSE OF THE STUDY A single treatment procedure for multi-fragmented non-reconstructible radial head fractures has not been established as of yet. One of the available treatment methods can be the implantation of an endoprosthesis, but there is no consensus in available publications. We therefore decided to trial their use and to obtain our own experience. This study includes the evaluation of the outcomes of treatment at one year postoperatively. MATERIAL AND METHODS Our group included eight patients (six men and two women with the mean age of 46.1 years, ranging from 24 to 80 years) with an implanted ExploR® (Biomet, U.S.A.) radial head endoprosthesis. The radial head fractures were of three to six fragment type, in six cases there was an associated dislocation. In one case, there was a concomitant diaphyseal fracture of the ulna which was stabilised using the Würzburger intramedullary nail (TRUE-Instrumente GmbH, Germany). The surgical approach through Kocher's interval was used in all cases. Fixation using a plaster splint from metacarpophalangeal joints up to the shoulder was applied postoperatively for a period of two to three weeks in all patients. RESULTS The assessment was carried out on average at 13 months (range 12-15 months) after the surgery. The mean elbow flexion was 7.5° to 136.9°, forearm supination was 0° to 86.3° and forearm pronation was 0° to 80.0°. The elbow joint maintained its stability in all cases. Neurological deficit did not develop in any of the patients. The DASH score reached the mean value of 11.2. The mean value of the Mayo Elbow Performance Score (MEPS) was 92.5. Radiological signs of implant loosening were observed in three cases. In two of these cases, bone resorption occurred surrounding the stem of endoprosthesis. In two patients, heterotopic ossification were found and in one case, an oversized endoprosthesis head was implanted. No recurrent elbow dislocation was seen in any of the patients. DISCUSSION The application of radial head endoprosthesis is indicated for comminuted radial head fractures and concurrent ligamentous injuries (fracture-dislocations, terrible triad, Essex-Lopresti injuries). Equally good functional outcomes may be achieved with the use of an endoprosthesis as by osteosynthesis. The complications of arthroplasty tend to be late, at ten or more years postoperatively. Further follow-up of our patients will be necessary, along with a further expansion of our group of patients. Complications may be prevented with the use of longer-stem implants and more up-to-date cemented bipolar endoprostheses which, according to recent studies, achieve equally good functional outcomes and reduce the number of necessary revision surgeries - implant removal in particular. CONCLUSIONS In treating the comminuted radial head fractures, the implantation of endoprosthesis helps to achieve a quick restoration of the elbow joint function along with good functional outcomes and prevents instabilities in case of associated ligamentous injuries. A basic precondition for successful treatment is the choice of an adequate size head. The radiological signs of stem loosening do not necessarily have to affect the functional outcomes. Key words: fracture, radial head, endoprosthesis, Kocher approach.

[Indication for Radial Head Resection in Traumatology]. / Indikace resekcí hlavic radia v traumatologii.

PURPOSE OF THE STUDY The aim of our study was to determine the indications for radial head resection at the present day. MATERIAL AND METHODS The radial head resection was performed in the period from 2008 to 2015 in 63 patients divided into three groups. The first group marked "CR" consisted of 33 patients with the Mason type III fracture. The second group marked "CRLUX" included 20 patients with the Mason-Johnston type IV fracture, i.e. a fracture of the proximal end of the radius with a dislocation of the elbow joint. Within this group, in 8 cases also the coronoid process of the ulna was fractured. The third group marked as "CRFR " was composed of 10 patients, in whom concomitant proximal radial fracture and proximal ulna fracture occurred, and in all the cases osteosynthesis of the proximal ulna fracture was performed. For subjective evaluation of the upper limb function the DASH score was used. The functional outcomes were expressed using the Mayo Elbow Performance Score (MEPS). Moreover, the range of motion in the elbow and forearm (flexion and extension of the elbow, pronation and supination of the forearm), elbow joint stability and presence of neurological lesions were assessed. The radiological assessment consisted of measuring the proximalization of the radius, monitoring the heterotopic ossifications, signs of arthrosis, recurrent re-dislocation of elbow and proximal ulna fracture healing. RESULTS The mean follow-up period was 17.6 months (range of 13.2 - 81.0 months, SD 11.5). The mean DASH score was 15.6 (range of 0 - 60, SD 15.3) in the CR group, 12.0 (range of 0 - 52.7, SD 16.7) in the CRLUX group and 17.5 (range of 0 - 62.3, SD 12.8) in the CRFRgroup. A considerably limited mobility was seen in the CR group in three cases (9.1%), in the CRLUX group in four cases (20.0 %) and in the CRFRgroup in two cases (20.0 %). The MEPS score showed similar results in all the groups, excellent and good results were always achieved in more than ¾ of patients. Elbow stiffness did not develop in any of the patients. In the CRLUXgroup, one case a re-dislocation of the elbow occurred. In the CRFRgroup, in one case an injury to the interosseous membrane and distal radioulnar joint ligaments failed to be diagnosed and a clinically significant proximalization of the radius (9 mm shift) occurred, which subsequently required ulnar shortening osteotomy. Additional two proximalization of the radius with a minor shift (2 and 3 mm) in the group CR and CRLUX were not associated with major mobility limitations. Heterotopic ossification occurred in a total of 11 cases (17.5 %) and in four cases it caused major mobility limitations (two cases in the CR group, one case in the CRLUX and CRFRgroups). Surgical treatment was indicated in one case with a good functional effect, in one case the range of motion improved after actinotherapy. In the CR group, one case of neuroma of the radial nerve developed and the condition was treated by sural nerve transplantation. DISCUSSION The current papers view simple proximal radial resection positively unless elbow instability is present. In literature, references are made to serious, mainly late complications (arthrosis, valgus deformity, considerable limitation of elbow range of motion, proximal radial-ulnar synostosis, proximalization of the radius and symptomatic radioulnar joint subluxation). Resection of the radial head is contraindicated in the so called "terrible triad" of the elbow, i.e. the combination of a radial head fracture, a coronoid process fracture and elbow dislocation, and in the Essex-Lopresti injury, i.e. a radial head fracture with a concomitant tear of the interosseous membrane of the forearm and radioulnar joint dislocation. The Essex-Lopresti injury is often overlooked during the initial examination, proximalization of the radius can occur gradually only after several months. CONCLUSIONS The evaluation of our groups of patients showed that the radial head resection can be a good treatment option with no serious early complications in the Mason type III fractures. Serious complications occurred only in cases when the fracture was accompanied by a concomitant injury, i.e. in the Mason-Johnson type IV fractures and in concomitant proximal ulna fracture. When an indication for radial head resection is made, it is essential to correctly diagnose the injury which is clearly a contraindication to this method, i.e. the Essex-Lopresti and the "terrible triad" injuries. Key words: fracture, radial head, resection.