Introduction and Objective. Several studies have described double and triple femoral neck lengthening osteotomies to correct coxa brevis deformity, however, no overview exists in literature. Our aim was to perform the first systematic review of the outcomes of double and triple femoral neck lengthening. Materials and Methods. After an extensive search in Pubmed, CINAHL and Embase libraries for published articles using the following search strategy: ‘(((proximal femoral deformity) OR hip dysplasia) OR coxa brevis) AND (((femoral neck lengthening) OR double proximal femoral osteotomy) OR triple proximal femoral osteotomy)’, we included studies reporting the results of double and triple femoral neck osteotomies. Clinical and radiological outcomes, and reported complications were extracted. The review process was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results. After evaluating 456 articles, we included 11 articles reporting 149 osteotomies in 143 patients (31% male, 64% female, 5% unspecified). Mean age of the patients was 20 years (range 7 years to 52 years). Indications were developmental hip dysplasia (51%), Perthes disease (27%), infection (6%), post-trauma (4%), congenital disorders (2%), slipped capital femoral epiphysis (1%), idiopathic (3%) and unknown (6%). The mean limb length discrepancy reduced by 12 mm (0 mm to 40 mm). In total, 65% of 101 positive Trendelenburg sign hips experienced improvement of abductor muscle strength. An 18% (9% to 36%) increase could be found in functional hip scores. Mean increase in articulo-trochanteric distance was 24 mm (10 mm to 34 mm). Five patients older than 30 years at the time of osteotomy and two younger patients with prior hip incongruency had disappointing results and required arthroplasty. In all, 12 complications occurred in 128 osteotomies, in which complications were reported. Conclusions. This first systematic review of double and triple femoral neck lengthening osteotomies shows that favorable outcomes and few complications can be expected in coxa brevis, however, excessive caution is required in older patients with
