Diabetic hip arthropathy is associated with a higher prevalence of femoral head chondromalacia: a case-controlled study

Patients Undergoing Microfracture With Allograft Cartilage and Autologous Platelet-Rich Plasma Augmentation for Chondromalacia in the Hip Achieving High Rates of Meaningful Outcomes at 2-Year Follow-Up

PURPOSE

To evaluate rates of achieving meaningful outcomes and clinical failure at 2 years after undergoing microfracture augmented with allograft cartilage with autologous platelet-rich plasma and to identify predictors of conversion to total hip arthroplasty (THA).

METHODS

Data from a prospective series of consecutive patients with Outerbridge grade 4 chondromalacia of the acetabulum or femoral head who underwent hip microfracture augmented with allograft cartilage between January 2017 and June 2022 were analyzed. Patient-reported outcomes were collected preoperatively and at a minimum of 2 years postoperatively. The Hip Outcome Score-Activities of Daily Living Subscale, Hip Outcome Score-Sports-Specific Subscale, modified Harris Hip Score, and Non-arthritic Hip Score thresholds for achieving the minimal clinically important difference, patient acceptable symptomatic state, and substantial clinical benefit at 2 years after surgery were calculated. Logistic regression analysis was performed to identify any association between nonmodifiable variables and clinical failure.

RESULTS

A total of 108 hips (80.6% follow-up) among 106 patients had 2-year follow-up and were included in the final analysis. The mean age and body mass index (BMI) were 37.9 ± 10.1 years and 26.8 ± 4.7, respectively, with a mean follow-up time of 31.9 ± 8.4 months (range, 24-53 months). There was a statistically significant improvement in all functional score averages over the 2-year period (P < .05). A total of 84.7%, 75.5%, and 70.4% of patients reached at least 1 threshold for achieving the minimal clinically important difference, patient acceptable symptomatic state, and substantial clinical benefit, respectively. There were 11 patients (10.2%) who underwent conversion to THA, with increased age, BMI, and preoperative pain duration increasing the likelihood of requiring THA (P < .05 for all). Finally, chondromalacia size or chondromalacia index (e.g., Outerbridge grade × surface area) was not associated with clinical failure or achievement of meaningful outcomes (P > .05 for all).

CONCLUSIONS

Patients undergoing microfracture with allograft cartilage and autologous platelet-rich plasma augmentation for acetabular or femoral head chondromalacia showed a statistically significant improvement in outcome scores and high rates of achieving meaningful outcomes at 2-year follow-up regardless of chondromalacia defect size. The rate of conversion to THA was 10.2%, with increased age, BMI, and preoperative pain duration increasing the likelihood of requiring THA.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Hip Arthroscopic Microfracture Augmented With Platelet-Rich Plasma-Infused Micronized Cartilage Allograft Significantly Improves Functional Outcomes

PURPOSE

To evaluate functional outcomes and survivorship in patients at 1 year after undergoing arthroscopic microfracture augmented with hyaline allograft for symptomatic chondral defects of the hip.

METHODS

Consecutive patients with and without prior hip procedures presenting with Outerbridge grade IV chondral lesion of the acetabulum or femoral head were prospectively followed. Patients underwent hip microfracture augmented with hyaline allograft suspended in autologous platelet-rich plasma between October 2016 and April 2018. Extent of cartilage degeneration was quantified using the chondromalacia severity index (CMI). Patient functional scores, including Tegner, Hip Outcome Score-Activities of Daily Living (HOS-ADL), Sport-Specific Subscale (HOS-SSS), modified Harris Hip Score (mHHS), and Nonarthritic Hip Score (NAHS) were collected preoperatively and at minimum 1-year postoperatively. Minimal clinically important difference (MCID) was analyzed. Statistical significance was established at P < .05. Pearson's coefficient analysis was performed to identify preoperative variables correlated with clinical outcomes.

RESULTS

Fifty-seven patients (86.4%) had minimum 1-year follow-up and were included in the final analysis, with a mean age and body mass index (BMI) of 38.3 ± 9.1 years and 27.7 ± 4.9 kg/m², respectively. Comparison of baseline and postoperative score averages demonstrated significant improvements in Tegner scores (3.7 ± 2.9 vs 5.1 ± 2.6; P = .003), HOS-ADL (63.3 ± 16.4 vs 89.1 ± 14.5; P < .001), HOS-SSS (40.8 ± 20.4 vs 79.5 ± 21.6; P < .001), mHHS (61.5 ± 16.2 vs 87.0 ± 17.7; P < .001), and NAHS (56.6 ± 14.9 vs 78.7 ± 18.3; P < .001). The percentage of patients who achieved MCID for HOS-ADL, HOS-SSS, mHHS, and NAHS were 89.8%, 83.0%, 75.6%, and 81.6%, respectively. Overall, 91.8% of patients met the threshold for achieving MCID in at least one outcome score. Of the 57 patients, 5 (8.8%) failed clinically, with 1 (1.8%) undergoing revision surgery and 4 (6.9%) undergoing conversion to total hip arthroplasty. There was a direct correlation between preoperative alpha angle and postoperative HOS-ADL. Femoral chondral lesion size and CMI inversely correlated with postoperative HOS-ADL.

CONCLUSIONS

Treatment of hip chondral defects with microfracture and hyaline allograft augmentation demonstrated excellent survivorship and significantly improved patient report outcomes at 1 year.

LEVEL OF EVIDENCE

IV, retrospective case series.