Background: Currently, total hip replacement (THR) is most commonly performed via a posterior or a direct lateral approach. We compared the one year postoperative outcome of cementless THR using the both approaches in a prospective, randomized trial.

Methods: A prospective 1:1 randomization scheme was implemented to allocate 60 patients with unilateral osteoarthritis. Patients in the lateral approach group were in median 59 years old, in 50% female and had a median BMI of 27 kg/m² versus in median 55 years, 47% females and a median BMI of 29 kg/m² in the posterior approach group. Outcome assessment was performed one day before surgery and 3 months, 6 months and one year after surgery, respectively, using the intra-individual Harris Hip score (HHS) improvement at one year as primary objective. Sample size calculation was based on the assumption of a minimum clinically relevant difference of 5 points and a standard deviation of 6 points in the HHS total score. WOMAC and SF-36 served as secondary objectives.

Results: Patients started with a median HHS of 50 points after lateral approach versus 46 points after posterior approach and showed a median HHS of 95 points versus 94 points one year after surgery. We found a slight tendency towards the posterior approach, but no significant difference in the intraindividual HHS improvement at all the pre- and post-operative assessment points between both treatment groups (Wilcoxon p=0.115 at 3 months, p=0.191 at 6 months and p=0.207 at one year). A comparable tendency was found in the intraindividual WOMAC improvement without statistical significance (Wilcoxon p=0.749). In contrast the SF-36 physical scales were slightly but again not significantly better after lateral approach at the one year assessment (86% versus 80%,Wilcoxon p=0.674).

Conclusions: Not any (algo-) functional and psychometric endpoint investigated showed a statistical significant difference between patients after lateral versus posterior approach for THR.

We conclude that motivation and other patient related factors, the implant and the surgeon itself influence the result much more than the approach used for total hip replacement.

Background: Correct rotational alignment of the femoral and tibial component is an important factor for successful TKA. The transepicondylar axis is widely accepted as a reference for the femoral component. There is no such reference for the tibial component. CT scans were used in this study to measure which tibial landmark most reliably reproduces a correct femoro-tibial rotational alignment in TKA. Furthermore, the impact of computer-assisted navigation on rotational alignment is investigated.

Materials and Methods: After informed consent, 80 patients were randomized to receive either navigated or conventional TKA. All patients received a cemented, unconstrained, cruciate-retaining TKA with a rotating platform. CT scans were performed 5–7 days postoperatively but before discharge. The rotational variance between the femoral and tibial components was measured.

Results: There was notable rotational variance between the femoral and tibial components in both groups. In the navigated group, the median variance was 1.2° relative external rotation of the femur (range: 16.2° relative external to 12.7° relative internal rotation of the femur). In the conventional group, the median variance was 1.7° relative internal rotation of the femur (range: 9.0° relative external to 14.4° relative internal rotation of the femur). Using the medial third of the tuberosity as reference for tibial rotational alignment, 67.5% of all TKA had a femoro-tibial variance within ± 5°, 85% within ± 10° and 97.5% within ± 20°. Using the medial border of the tibial tubercle as reference this variance was greater, 3.8% had a femoro-tibial variance within ± 5°, 15% within ± 10° and 68.8% within ± 20°.

Conclusion: Using fixed bone landmarks for rotational alignment leads to a notable variance between femoral and tibial component. Computer-assisted navigation did not reduce this variance.

Referencing the tibial rotation on a line from the lateral border of the medial third of the tibial tubercle to the center of the tibial tray resulted in a better femoro-tibial alignment than using the medial border of tibial tubercle as landmark. Surgeons using fixed bearings with a high conformity between the inlay and the femoral component should be aware of this effect to avoid premature polyethylene wear.

Background: Computer-assisted navigation systems are supposed to improve the precision of implant positioning and therefore the longevity of the knee arthroplasty. Several studies have demonstrated a better mechanical axis or axial component alignment in navigated compared to conventional TKA at least less outliers from a range of 3° of varus or valgus. It is still unclear wether navigation can improve rotational alignment.

Materials and Methods: After informed consent 80 patients were randomized to navigated or conventional TKA. In all patients, a cemented, unconstrained, cruciate-retaining TKA with a rotating platform was implanted. A full-length standing and a lateral radiograph and CT Scans of the hip, knee and ankle joint were done 5 to 7 days postoperatively before discharge.

Results: The navigated group showed a median deviation from the mechanical axis of 1,5° with a range between 5,9° valgus and 4,6 varus malalignment. The conventional implanted arthroplasties showed a median deviation from the mechanical axis of 1,6° with a range between 5,9° valgus and 7,2° varus malalignment. 5 navigated and 7 conventional implanted arthroplasties were outside a tolerance level of 3°.

The femoral component showed a median deviation from the transepicondylar axis of 1,7° (range: 3,1° external rotation to 4,4° internal rotation) in the navigated group and of 1,0° (range: 3,4° external rotation to 4,3° internal rotation) in the conventional implantations.

The tibial component showed a much greater range of rotational deviation from the medial third of the tuberosity in median 5,3° (range: 14,9° external rotation to 26° internal rotation) in the navigated group and 4,8° (range: 6,5° external rotation to 23,8° internal rotation) in the conventional implantations.

Conclusion: We could not find a difference between Computer-assisted navigation and conventional implantation for rotational alignment of the femoral or tibial component. While the deviation from the transepicondylar axis was quite low and nearly all implantations were within a range of 3° of internal and external rotation there was a considerable range of deviation for the tibial rotational alignment.

Purpose: Although arthroscopic Bankart repair is yet an established procedure in the treatment of traumatic anterior shoulder instability, it is still not known whether it reproduces the good results of the open repair procedure. Aim of this investigation was to compare the functional and subjective outcome between open and arthroscopic Bankart repair.

Material and methods: A retrospective cross sectional study design on the comparison of open and arthoscopic Bankart treatments between 1995 and 2004 was implemented at the Dresden Orthopedic Surgery Department. In this period a total of 223 patients underwent surgery due to anterior shoulder instability, among which 212 patients had posttraumatic instability. A diagnostic arthroscopy was performed in all patients, but only 40 patients with intact capsulolabral complex and without capsular laxity were treated arthroscopically, the remaining 183 patients underwent an open Bankart procedure.

A total of 186 patients with posttraumatic anterior instability could be clinically re-examined within 1 to 5 years after initial surgery, among which 147 patients underwent an open and 39 patients an arthroscopic Bankart procedure. The median age of this sample was 27 years (interquartile range 21 – 37 years) at initial surgery, 21% of these patients were female.

Results: After open surgery 11 of 147 patients (8%) and 6 of 39 (15%) after arthroscopic surgery reported one or more re-dislocation after initial treatment, which occurred after a mean dislocation free time of 62 versus 40 months, respectively (95% confidence intervals 59 – 65 versus 36 – 44 months). Both a univariate analysis (Logrank test p=0.012) and a multivariate Cox regression analysis (Likelihood Ratio p=0.023) confirmed a statistically significant difference in the time between initial surgery to first reluxation. 4 of the 11 re-dislocations after open and 1 of 6 after arthroscopic surgery occurred after a new accident. That makes a re-dislocation rate without new adequate trauma of 5% after open and 13% after arthroscopic treatment.

ROM showed no difference between open and arthroscopic Bankart procedure for abduction and a mild difference for external rotation. 21 of 115 (18%) patients had an external rotation lag of 20° or more after open surgery versus 1 of 34 (3%) after arthroscopic treatment (Fisher p=0,027). The Rowe score demonstrated “good” or “excellent” functional results in 102 of 117 (87%) patients versus 28 of 35 (80%) patients after open versus arthroscopic treatment (Fisher p=0,285).

Conclusion: In this sample arthroscopic Bankart repair demonstrated more frequently and significantly earlier re-dislocation after initial surgery than did the open treatment alternative. External rotation lags of at least 20° occured more frequently after the open procedure.