According to a study from Harvard Medical School, your experience may be fairly typical. In fact, many studies have been done on patients who have had open incision carpal tunnel release surgery. The results have shown that symptoms improve right away but it can take months for patients to recover strength and function. Some studies show that slightly more than half of all patients report a recurrence of hand pain, numbness, and tingling two years after surgery.
What happens 10 years later is the subject of the study from Harvard Medical School in Boston, Massachusetts. One (fellowship-trained) hand surgeon who had performed 211 open carpal tunnel releases contacted his patients 11 to 17 years after the procedure. Using a series of self-assessment surveys, symptoms, function, and patient satisfaction were measured.
The patients included adults of all ages from under fifty years of age to sixty and older. There were adults who were actively employed and working, retirees, and pre-and postmenopausal women. They discovered that three-fourths of the group no longer had any carpal tunnel problems. Most of the problematic symptoms went away in the first year after the surgery. Almost 90 per cent (88 per cent to be exact) were very satisfied or completely satisfied with the results.
For the people who still had some symptoms of carpal tunnel syndrome, the most common symptom was hand weakness (e.g., grip and pinch strength, difficulty opening jars or holding a book). Daytime pain, numbness, and tingling were also reported by a few people.
Patients who had the most difficulty years later were those who also had diabetes, rheumatoid arthritis, osteoarthritis, or polyneuropathy. All of these conditions are linked with carpal tunnel syndrome. It is likely that the problems encountered with functional tasks was really related more to these comorbidities (other conditions) than the after-effects of carpal tunnel surgery.
Only two of the patients had to have a second (repeat) surgery. And only a few patients had pain at night or tenderness along the (healed) incision line. Analysis of all the data did not show any particular pain patterns associated with age. But function was worse in the middle age group (ages 50 to 59). The reason(s) for the connection between middle ages and worse function were unknown. It’s possible that the older age group had worse function but accept their limitations and/or have fewer physical demands placed on them so the loss of function is not as noticeable.
This is one of the few long-term studies of results following open carpal tunnel release. As you mentioned, more carpal tunnel surgeries are done endoscopically now with minimally invasive techniques. But the results for patients who had open-incision carpal tunnel releases clearly show that excellent early improvements are maintained over the long-term with equally excellent reports of patient satisfaction and improved quality of life.