Influence of Fatty Infiltration on Hip Abductor Repair Outcomes: A Systematic Review and Meta-analysis.

Abstract

Increasing evidence supports surgical intervention for hip abductor tears; however, the influence of fatty infiltration (FI) on outcomes after repair remains uncertain and has been addressed only in small case series. To clarify the relationship between FI and surgical outcomes for hip abductor tears. Meta-analysis; Level of evidence, 4. A systematic review and meta-analysis was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. FI severity was assessed by Goutallier-Fuchs (G-F) grade. The relationship between FI and improvement in Harris Hip Score (HHS)/modified Harris Hip Score (mHHS) and visual analog scale (VAS) score for pain was examined with mixed-effects metaregression. Outcomes with open and endoscopic techniques were also compared. A total of 4 studies (206 repairs in 201 patients) were eligible. High-grade FI was associated with significantly less improvement in HHS/mHHS than both no FI (6.761 less; 95% CI, 3.983-11.570; <i>P</i> = .002) and low-grade FI (7.776 less; 95% CI, 2.460-11.062; <i>P</i> < .001) but did not significantly influence VAS score (<i>P</i> > .05). Controlling for FI severity, we found no significant difference in HHS/mHHS improvement between open versus endoscopic repair (<i>P</i> > .05 at each level), but open repair resulted in significantly greater improvement in VAS score for every G-F grade (all <i>P</i> < .005). Surgical intervention for symptomatic hip abductor tendon tears improved outcomes as reflected by change in HHS/mHHS; however, the presence of high-grade FI resulted in less improvement. FI severity did not influence VAS scores for pain. Although no differences were found between open and endoscopic repairs in terms of FI-adjusted improvement in HHS/mHHS, open repairs resulted in significantly greater pain relief at each FI level.