High incidence of intraoperative calcar fractures with the cementless CLS Spotorno stem.

INTRODUCTION: This study reports on the incidence of intraoperative calcar fractures with the cementless Spotorno (CLS) stem, and the potential role of a learning curve and implant positioning is investigated. METHODS: After introduction of the CLS stem, 800 consecutive cementless total hip arthroplasties (THA) were analyzed. The incidence of calcar fracture in the first 400 THA was compared with the second 400 THA, in order to study a potential learning curve effect. According to the instruction for users, varus positioning of the stem was avoided and a femoral neck osteotomy was aimed relatively close to the lesser trochanter since these are assumed to be correlated with calcar fractures. Implant positioning (neck-shaft angle, femoral offset and osteotomy-lesser trochanter distance) was measured on postoperative pelvic radiographs of all THA with calcar fractures and 100 randomly selected uncomplicated control cases. RESULTS: Seventeen (2.1%) intraoperative calcar fractures were recorded. The incidence of calcar fracture differed between the first 400 THA (n = 11) and the second 400 THA (n = 6). This difference was not statistically significant (p = 0.220); however, these numbers indicate a trend toward a learning effect. No significant difference in stem positioning nor the height of the femoral neck osteotomy was measured between THA with a calcar fracture (n = 17) and the control cases (n = 100). CONCLUSIONS: We report on a high incidence of intraoperative calcar fractures with the use of a CLS stem. The risk for calcar fractures remains clinically significant even after adequate implant positioning in the hands of experienced hip surgeons. Surgeons should be aware of this implant related phenomenon and be alert on this phenomenon intraoperatively.

Systematic review: lack of evidence for the success of revision arthroplasty outcome in younger patients.

INTRODUCTION: Total hip arthroplasties (THAs) in younger patients are becoming increasingly popular. However, the outcome of subsequent revisions in younger patients is not well known and, therefore, their success (subsequent revision prosthesis survival) might be overestimated. We investigated available data on the outcome of primary- and subsequent revision THAs performed in the same cohort of patients who underwent primary THA under the age of 50. METHODS: Medline, Embase and the Cochrane Library (CENTRAL) were searched up until April 13, 2016 for studies that reported both the survival of primary and subsequent revisions THA of single cohorts of patients younger than 50. Eligible articles had to include Kaplan Meier analysis or competing risk analysis for survival of the primary THA at a mean follow-up of 10 years, as well as for the subsequent revision THA within the same cohort. RESULTS: We found 4,799 unique records; 43 of which were potentially eligible. Only 1 paper met our inclusion criteria. It reported on the survival of 69 primary prostheses at a mean of more than 10 years follow-up and 13 subsequent revisions. CONCLUSIONS: There is a clear lack of evidence about the outcomes of the revision arthroplasty in younger patients. Only 1 study reported the survival-rate of subsequent revision arthroplasty with the minimum 10-year survival rate of the original THA cohort. In the future, this serious lack of knowledge could result in a large number of patients with no further reconstructive options after failed THA, and a large medical burden for society.