A distal biceps rupture occurs when the tendon attaching the biceps muscle to the elbow is torn from the bone. This injury occurs mainly in middle-aged men during heavy work or lifting. A distal biceps rupture is rare compared to ruptures where the top of the biceps connects at the shoulder. It is estimated that distal biceps ruptures make up between three and 10 percent of all biceps tendon ruptures.
The biceps muscle goes from the shoulder to the elbow on the front of the upper arm. Tendons attach muscles to bone. Two separate tendons connect the upper part of the biceps muscle to the shoulder. One tendon connects the lower end of the biceps to the elbow.
The lower biceps tendon is called the distal biceps tendon. The word distal means that the tendon is further down the arm. The upper two tendons of the biceps are called the proximal biceps tendons, because they are closer to the top of the arm.
The distal biceps tendon attaches to a small bump on the radius bone of the forearm. This small bony bump is called the radial tuberosity. Surgery to repair the tear brings the torn end of the tendon back to the bump if possible. If the tear is too extensive and the arm has to be bent 70 degrees or more to bring the torn end back to the bone, then a tendon graft is used to extend the tendon long enough to reattach it to the radial tuberosity.
Many patients are content to let the torn tendon heal where it retracts (pulls back) to. But if cramping continues or the loss of strength affects daily function, then surgery is advised. Surgery is not without possible problems and patients need to be aware of what those complications might be. That’s what this study offers.
Surgeons from four large sites in Florida combined their research efforts to create a large patient data base. A total of 178 medical files of patients were reviewed. Each patient had a distal biceps tendon surgical repair. Only those patients who had a fracture, elbow dislocation, or traumatic laceration (cut) to the biceps were excluded from the study.
Information collected from the patient charts included age, sex (male or female), time between injury and surgery, surgical technique used, and post-operative complications. Anyone who had surgery 30 or more days after the injury was considered to have a chronic injury. Those patients who had surgical repair in the first 29 days after injury were labeled acute.
The problems that developed after surgery were divided into two categories: minor and major. Analysis of the information collected showed that slightly more than one-third (36 per cent) of all patients experienced some problems after surgery. Most of these were minor and temporary. Numbness from nerve injury and skin infections were the most common minor complications.
Major complications occurred much less often (eight per cent of the total) and included more serious nerve injury, painful heterotropic ossification, and rerupture. Heterotropic ossification refers to the formation of bone tissue in the tendon and muscle causing stiffness, loss of motion, and pain. Most of the reruptures were caused by trauma because of patients who did not follow the surgeon’s instructions.
Although there were five different surgeons who did the surgeries, there were no significant differences in results from one to another. The number of complications was the same no matter what surgical approach or technique was used. Patients with chronic injuries had slightly higher rates of postoperative problems but not enough to be considered statistically significant.
Even though the study had more patients (178) than most other studies examining complication rates after distal biceps tendon repair, some of the factors weren’t found to be significant. That’s because statistically speaking, there weren’t enough people in the study for full analysis. For example, the use of a tendon graft and chronic injuries that were years (not months) old might be risk factors or predictive factors for complications.
This study is important because it helps surgeons see what might be causing problems after surgery for distal biceps tendon rupture and therefore, prevent such events from happening. If it looks like the procedure is too risky due to the possibility of damage to nearby blood vessels and nerves, then the surgeon might advise the patient to avoid surgery and treat the problem conservatively.
And knowing that more chronic injuries have a greater chance of significant complications may assist surgeons in planning earlier surgical repairs. Whenever possible, surgery should be done within the first 30 days after injury.
This series confirms what other studies have shown in that chronic injuries (repaired more than 30 days later) have the highest rate of postoperative complications. It’s easier for the surgeon to find the end of the torn tendon, pull it back to the bone where it belongs, and reattach it if the procedure is done before scar tissue and contracture (stiffness) occurs at the tendon/muscle interface.