Does lateral incision reduce perceptual deficits and improve postoperative kneeling ability after total knee arthroplasty?

Purpose

Kneeling is often difficult after a total knee arthroplasty. However, the reasons behind kneeling difficulties are not yet fully understood. According to several studies, a lateral incision reduces perceptual deficits and improves kneeling performance. This study compared two different skin incisions (lateral and midline) as they relate to postoperative perceptual deficits, as well as kneeling on a mat or in daily life following TKA, and demonstrates the advantage of the lateral incision in postoperative kneeling ability.

Methods

This study included 99 patients with lateral incisions and 104 patients with midline incisions. Sensory disturbance was evaluated with a brush on the nine subdivisions of the kneeling area. Patients were tested in the outpatient clinic to determine whether they could kneel on a mat. The level of discomfort in the kneeling area was assessed using a visual analog scale. Questionnaires were used to assess kneeling ability.

Results

Compared to a midline incision, a lateral incision significantly reduced the perceptual deficits in the center of the kneeling area and the discomfort associated with kneeling on a mat. There was no significant difference between the two groups in kneeling on a mat in the clinic or kneeling in daily activities. However, less than 30% of patients in both groups could kneel in daily living. The reasons for being unable to kneel were mainly anxiety and pain, rather than numbness.

Conclusion

Lateral incisions alone did not improve kneeling in patients' daily living following TKA.