桡骨小头置换治疗Mason Ⅲ型桡骨小头骨折的临床疗效观察

The preliminary clinical efficacy of treatment for Mason type-Ⅲ radial head fractures with radial head arthroplasty

目的：探讨采用桡骨小头置换治疗 Mason Ⅲ型桡骨小头骨折早期临床疗效。方法对2010年3月至2013年3月我院收治的9例 Mason Ⅲ型桡骨小头骨折患者予以桡骨小头置换，采用Broberg和 Morrey的肘关节功能评分标准，评价术后早期疗效。结果患者全部得到随访，术后随访6~36个月，平均19.6个月，优5例、良3例、中1例，本组病例随访时均未发现肘关节感染、强直或脱位，慢性肘关节炎及肘、前臂和腕部长期慢性疼痛等并发症。结论桡骨小头置换治疗 MasonⅢ型桡骨小头骨折早期临床疗效良好，远期疗效有待进一步评价。

Background Comminuted radial head fractures were difficult to treat with open reduction and internal fixation.Radial head arthroplasty was a favourable technique for the treatment of complex radial head fractures.The purpose of this study was to evaluate the early clinical efficacy of radial head arthroplasty for the treatment of Mason type-Ⅲ radial head fractures.Methods We retrospectively reviewed 9patients who suffered from Mason type-Ⅲ radial head fractures requiring radial head arthroplasty between March 2010 and March 2013.In these nine patients,There were 6female and 3 male with mean age 29.4(24-36years),7patients combined with medial collateral ligament injury and interosseous membrane damage,two patients combined fractures of the proximal ulna.According to Mason classification,Fractures of the radial head had been classified as follow,typeⅠ:radial head or neck fracture,with no or minimal displacement;TypeⅡ:radial head or neck fracture,fracture displacement >2 mm;Type Ⅲ:Severe comminuted radial head and radial neck fractures;Type IV:If the patients associated with dislocation of the elbow and forearm interosseous membrane damage,the typeⅢ fractures may be referred to Mason Johnston type IV.All of the nine patients were Mason Johnston typeⅢ.Surgical technique as follows:After the success of the brachial plexus or general anesthesia,a tourniquet was tied up to the ipsilateral arm,then the routine disinfection and draping were performed. We used the Kocher approach to open the skin and subcutaneous tissue,the incision was about 6 ~ 8cm,Then,through the interval between the anconeus and the extensor carpiulnaris(ECU)to expose the lateral capsule of the elbow.During the operation,the forearm pronation should be kept to protect the posterior interosseous nerve.Identified the head fracture,and we removed all fragments of the unreconstructable head.A cutting guide was used in order to achieve a good resection,which must be perpendicular to the axis of the radius.The parts of the broken head were reassembled on the table to ensure that the whole head had been resected and to choose the size of the prosthetic head.After resection of the radial head,the radial shaft was prepared.Then the trial stem was introduced and left temporarily in place.The positioning and height of the prosthesis are essential for the success of the implantation.The head had to reach the limit between the trochlear notch and the radial notch of the ulna.X-rays were performed to check proper choice of the elements sizes,the positioning of the neck and the height of the prosthesis.The proximal concave of the trial prosthesis is toward lateral side,so that the direction of the trial prosthesis was unanimous with the normal anatomy of the radial head.After installation of the trial prosthesis,reset the elbow joint,then checked the stability.If the size and the position were appropriate,the trial prosthesis was removed and the wound was irrigated.After removal of trial elements,the suitable Swanson prosthesis was inserted.Direction was toward the outside of the proximal articular surface,reset,check the joint stability again,passive elbow and forearm,and make sure there were no collision occured between the artificial radial head and surrounding soft tissue or bone structure,the contact between the humeral head and prosthesis must be good,so that the prosthesis can be well covered in the proximal radius,The height of the implant must keep 2mm spacing between the prosthesis and the humeral head cartilage surface.If an anterior capsule tearing or annular ligament and lateral collateral ligament complex injury were present,the surgeon repaired it at this time.Then washed the wound,placed drainage tube,sutured the incision.Antibiotics were routinely used to prevent infection after surgery.The drainage tube would be removed within 48 hours,ice compress was used to release local edema.Passive range of motion exercise was peformed 3~5days after surgery,active motion of the elbow joint was allowed 14 days after surgery,rotational activities must be carried out under conditions of 90 degrees of elbow flexion.The non-steroidal anti-inflammatory drugs were given to prevent myositis ossificans postoperatively.Functional outcomes were assessed by the Broberg and Morrey elbow function grading standards.Results All of the 9patients were performed 6-36 months follow-up,The mean follow-up time was 19.6 months.Five patients had an excellent result;3,a good result;and 1,a fair result,according to the Broberg and Morrey elbow functional grading standards.During the follow-up,we did not find any postoperative complications,such as elbow dislocation,infection,stiffness,or chronic arthritis and elbow,chronic pain of forearm and wrist.Discussion Treatment of comminuted fractures of the radial head was controversial,and considerable effort has been made to restore optimal function of the elbows,either by surgical repair or prosthetic replacement.Radial head arthroplasty was an acceptable option when treating Mason type-Ⅲ radial head fractures,and the early clinical curative effect was good.But a larger group of patients and a longer follow-up period will be required in order to estimate the long-term curative effect.However,none of the patients who underwent this procedure showed any complications during follow-up.