Compression nailing for posttraumatic rotational femoral deformities: open versus minimally invasive technique

Intraoperative control by Schanz-screws is inaccurate to achieve the exact amount of correction in de-rotational osteotomies

PURPOSE

The accuracy of intraoperative control of correction commonly is achieved by K-wires or Schanz-screws in combination with goniometer in de-rotational osteotomies. The purpose of this study is to investigate the accuracy of intraoperative torsional control in de-rotational femoral and tibial osteotomies. It is hypothesized, that intraoperative control by Schanz-screws and goniometer in de-rotational osteotomies around the knee is a safe and well predictable method to control the surgical torsional correction intraoperatively.

METHODS

55 consecutive osteotomies around the knee joint were registered, 28 femoral and 27 tibial. The indication for osteotomy was femoral or tibial torsional deformity with the clinical occurrence of patellofemoral maltracking or PFI. Pre- and postoperative torsions were measured according to the method of Waidelich on computed tomography (CT) scan. The scheduled value of torsional correction was defined by the surgeon preoperatively. Intraoperative control of torsional correction was achieved by 5 mm-Schanz-screws and goniometer. The measured values of torsional CT scan were compared to the preoperative defined and intended values and deviation was calculated separately for femoral and tibial osteotomies.

RESULTS

The surgeon's intraoperative measured mean value of correction in all osteotomies was 15.2° (SD 4.6; range 10-27), whereas the postoperatively measured mean value on CT scan was 15.6 (6.8; 5.0-28.5). Intraoperatively the femoral mean value measured 17.9° (4.9; 10-27) and 12.4° (1.9; 10-15) for the tibia. Postoperatively the mean value for femoral correction was 19.8 (5.5; 9.0-28.5) and 11.3 (5.0; 5.0-26.0) for tibial correction. When considering a deviation of plus or minus 3° to be acceptable femorally 15 osteotomies (53.6%) and tibially 14 osteotomies (51.9%) fell within these limits. Nine femoral cases (32.1.%) were overcorrected, four cases undercorrected (14.3%). Four tibial cases of overcorrection (14.8%) and 9 tibial cases of undercorrection (33.3%) were observed. However, the observed difference between femur and tibia regarding the distribution of cases between the three groups did not reach significance. Moreover, there was no correlation between the extent of correction and the deviation from the intended result.

CONCLUSION

The use of Schanz-screws and goniometer in de-rotational osteotomies as an intraoperative control of correction is an inaccurate method. Every surgeon performing derotational osteotomies must consider this and include postoperative torsional measurement in his postoperative algorithm until new tools or devices are available to guarantee a better intraoperative accuracy of torsional correction.

STUDY DESIGN

Observational study.

LEVEL OF EVIDENCE

III.

Retrograde Intramedullary Nail Fixation for Derotational Femoral Osteotomy for Recurrent Femoropatellar Instability

Axial alignment of the femur and tibia is often misdiagnosed in patients with patellofemoral stability problems. Femoral torsion is critical for patellofemoral biomechanics, so it must be evaluated in every patient before the plan of surgery is decided. This case describes a femoral derotational osteotomy due to excessive internal torsion of the femur fixed with a retrograde femoral nail. This type of fixation provides a biomechanical advantage compared to plates. At the two-year follow-up, the patient achieved excellent results, reaching a functional score of 91 points on the Lysholm scale. Derotational femoral osteotomy should be considered in patellofemoral pathology, and a retrograde femoral nail is a valid fixation method for this surgery.

The applied anatomy of anterior approach for minimally invasive hip joint surgery

The anterior approach for minimally invasive hip joint surgery is one of the common approaches utilized in hip joint surgery. Here, we report the results of dissections in 60 sides of human adult cadavers. We observed and measured the branches of the superficial circumflex iliac artery, the lateral femoral cutaneous nerves, the lateral circumflex femoral artery, and the superior gluteal nerves in the experiment via the anterior approach for minimally invasive hip joint surgery. The relationship between these structures and the anterior approach was studied. The present study provides important data demonstrating the location, path of dominant structures that might be encountered during the surgery and their relationships with the surgical incision. These data may allow surgeons performing the anterior approach for hip joint surgery to minimize the risk of neurovascular injury.

Long-term effects of saw osteotomy versus random fracturing on bone healing and remodeling in a sheep tibia model

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Subtrochanteric derotation osteotomy using a bent dynamic compression plate in children with medial femoral torsion

Subtrochanteric osteotomy of the femur using a bent dynamic compression plate is a simple, safe, and stable technique for correction of severe medial femoral torsion.