A recent study published in the American journal “American Journal of Sports Medicine” set out to assess the results of arthroscopic treatment of femoroacetabular impingement and of tears of the labrum of the acetabulum in patients with mild osteoarthritis (Tönnis grade 1) over five years of follow-up, and to compare them with a control group whose hip radiographs were Tönnis grade 0. The study was carried out because there are not many studies on the treatment of femoroacetabular impingement and of tears of the labrum of the acetabulum in mild osteoarthritis.
The study was a cohort study at level 3 of evidence. Data were collected prospectively on patients who underwent hip arthroscopy between February 2008 and April 2011. The criteria for including patients were arthroscopic treatment for femoroacetabular impingement and for tears of the labrum of the acetabulum, which were assessed clinically with the Harris Hip Score, the Non-Arthritic Hip Score, the Hip Outcome Score-Sports-Specific Subscale and a visual analog scale. The criteria for exclusion from the study were Tönnis grade 2 osteoarthritis and previous disorders of the hips (surgery on the opposite limb, slipped capital femoral epiphysis, avascular necrosis of the femoral head and hip dysplasia). Patients with a minimum follow-up of five years whose hip radiographs were Tönnis grade 0 were identified and compared with the control group. Of the 356 hips, 292 had five-year results (82%). Eighty-five Tönnis grade 1 hips were assessed. At five-year follow-up the patients with Tönnis grade 1 showed significant improvement on all the assessment scales. Survivorship with respect to conversion to total hip arthroplasty was 69.4% at five years for the Tönnis grade 1 group, and 88.4% for the Tönnis grade 0 group. Sixty-two Tönnis grade 0 hips were compared with 62 Tönnis grade 1 hips. Both groups showed improvement on all the assessment scales postoperatively compared with their preoperative state. There were no statistically significant differences between the preoperative and postoperative scores, or in survivorship, between the groups.
The study concluded that arthroscopic treatment for femoroacetabular impingement and for a tear of the labrum in patients with Tönnis grade 1 gives good results at five-year follow-up. The comparison showed that patients with Tönnis grade 1 had similar improvement, lasting just as long, as those with grade 1. Although specific surgical indications and appropriate expectations are recommended for patients with mild osteoarthritis, patients with Tönnis grade 1 osteoarthritis should not be regarded as having a contraindication to arthroscopic hip surgery.
Source: Domb BG, Chaharbakhshi EO, Rybalko D, Close MR, Litrenta J, Perets I. Outcomes of Hip Arthroscopic Surgery in Patients With Tönnis Grade 1 Osteoarthritis at a Minimum 5-Year Follow-up: A Matched-Pair Comparison With a Tönnis Grade 0 Control Group. Am J Sports Med. 2017.
