Though rupture of the distal biceps tendon was earlier reported to be around 3% of all biceps tendon ruptures, it has been recently estimated to be closer to 10%.24,25
Prior to 1995, there were 53 published articles concerning the distal biceps, in contrast to more than 70 new publications on this topic over the past 3 years, reflecting an incidence trend or a possible increase in detection.1
The patients are usually able to perform unhampered activities of daily living with some weakness and fatigability of the supination movement (e.g. using a screw driver) on a long followup when treated non-surgically.1
This is the probable reason that the patients with sedentary occupations do not usually visit the specialized centers and the incidence of the injuries is under reported. The professional sportspersons do not neglect injuries, hence a higher rates of detection of the injuries. Seven of the eight patients included in our series were referred to us specifically for the surgical treatment by the sports physicians who initially provided first aid to the patients.
The asymmetrical contours of the biceps muscle bellies on the two sides and on palpation of a relatively proximally situated muscle belly of the ruptured biceps led us to diagnose it. Hook test was positive in all the cases. The sensitivity and specificity of clinical examination has earlier been reported to be 100% in comparison to 92% sensitivity and 85% specificity of magnetic resonance imaging (MRI).5,26
Furthermore, the musculoskeletal radiologist performing MRI examination on such patients ought to be aware of the fact that proper visualization of the distal biceps tendon with MRI requires a special flexed abducted supinated (FABS) position of the upper limb, which includes 90° of elbow flexion, 180° of shoulder abduction and forearm supination.27
A thorough and complete clinical examination is of utmost importance to make an early diagnosis especially in sportspersons because a delay in the diagnosis and treatment can result in loss of their sports career.28
We intended to use minimal invasive technique to the best of our ability. In one case we faced difficulty in retrieving the retracted biceps tendon through the small distal incision, we used arthroscopy through the distal incision to retrieve the tendon. Since the majority of the patients were competitive sports persons in our series, who belonged to bodybuilding, wrestling, weightlifting, etc., minimal invasive technique was supposed to give them the advantage of early functional recovery as well as cosmetic esthesis. In a comparative prospective study of the single versus double surgical incision techniques, El Hawary et al
. have reported the results of the single-incision surgical technique to be superior at 1-year follow-up, but with a higher rate of complications.29
In a systematic review of distal biceps tendon repairs, Chavan et al. have reported a significantly higher rate of unsatisfactory surgical outcomes of the two incision technique in comparison to the single-incision technique, while the endobutton fixation was reported to give the best biomechanical performance in terms of stiffness and load failure.15
However, the authors reported a high rate of complication to the tune of 18% in one incision technique, with the most common complication being nerve injury that was reported in 13% of the patients.15
Taking the advantage of the higher success rate of the single incision technique and the best biomechanical strength of the endobutton, we were able to altogether avoid the complication of nerve injury in our series with the present surgical technique using a blunt tipped needle. The nick used by us on the tented skin posteriorly to facilitate the passage of the blunt tipped needle was placed only in the skin and was not a formal second incision used in the standard two incision technique for the surgical exposure of the proximal radius from the posterior side10
Peters et al
. have reported a malposition of the endobutton in three of the nine patients, but without a significant difference in the functional outcome; although ultimately they had to remove one malpositioned endobutton.30
We routinely see the position of the endobutton fluoroscopically by rotating the forearm in full supination and pronation at the end of the procedure. In one patient, we had to use an additional posterior surgical nick to adjust the position of the endobutton that was found to be lying subcutaneously on fluoroscopic examination.
We did not observe the complication of heterotopic ossification or radioulnar synostosis in any of the patients in our series. We mainly attribute this to copious irrigation of the wound with saline to wash out any bone dust generated as a result of drilling and burring of the proximal radius. Moreover, we did not dissect in the radioulnar interval at all that would predispose the formation of a radioulnar synostosis. We did not use any additional agent postoperatively to prevent the incidence of heterotopic ossification.
Both DASH scores and Mayo elbow performance score have been individually used in the literature to assess the outcome after the surgical repair of torn biceps tendon.30,31
We used both the tools in the present series and they correlated well with each other and also with the final function of the patient.
In conclusion, we feel that the single incision surgical technique used by us with a blunt tipped pin to facilitate the passage of endobutton to repair torn distal biceps tendon is a simple, safe and effective technique with excellent results.