Association between the appropriateness of surgery, according to appropriate use criteria, and patient-rated outcomes after surgery for lumbar degenerative spondylolisthesis.

INTRODUCTION: Treatment failures in spine surgery are often attributable to poor patient selection and the application of inappropriate treatment. We used published appropriate use criteria (AUC) to evaluate the appropriateness of surgery in a large group of patients operated for lumbar degenerative spondylolisthesis (LDS) and to evaluate its association with outcome. METHODS: This was a retrospective analysis of prospectively collected outcome data from patients operated in our Spine Centre, 2005-2012. Appropriateness of surgery was judged based on the AUC. Patients had completed the multidimensional Core Outcome Measures Index (COMI) before surgery and at 3 months' and 1, 2 and 5 years' follow-up (FU). RESULTS: In total, 448 patients (69.8 ± 9.6 years; 323 (72%) women) were eligible for inclusion and the AUC could be applied in 393 (88%) of these. Surgery was considered appropriate (A) in 234 (59%) of the patients, uncertain/equivocal (U) in 90 (23%) and inappropriate (I) in 69 (18%). A/U patients had significantly (p < 0.05) greater improvements in COMI than I patients at each FU time point. The minimal clinically important change (MCIC) score for COMI was reached by 82% A, 76% U and 54% I patients at 1-year FU (p < 0.001, I vs A and U); the odds of achieving MCIC were 3-4 times greater in A/U patients than in I patients. CONCLUSIONS: The results suggest a relationship between appropriateness of surgery for LDS and the improvements in COMI score after surgery. The findings require confirmation in prospective studies that also include a control group of non-operated patients.

Contact force path in total hip arthroplasty: effect of cup medialisation in a whole-body simulation.

BACKGROUND: Cup medialisation down to the true acetabular floor in total hip arthroplasty with a compensatory femoral offset increase seems to be mechanically advantageous for the abductor muscles due to the relocation of the lever arms (body weight lever arm decreased, abductor lever arm increased). However, limited information is currently available about the effects of this reconstruction type at the head cup interface, compared to an anatomical reconstruction that maintains the natural lever arms. Through a whole-body simulation analysis, we compared medialised versus anatomical reconstruction in THA to analyse the effects on: (1) contact force magnitude at the head cup interface; (2) contact force path in the cup; and (3) abductor activity. METHODS: Musculoskeletal simulations were performed to calculate the above-mentioned parameters using inverse dynamics analysis. The differences between the virtually implanted THAs were calculated to compare the medialised versus anatomical reconstruction. RESULTS: Cup medialisation with compensatory femoral offset increase led to: (1) a reduction in contact force magnitude at the head cup interface up to 6.6%; (2) a similar contact force path in the cup in terms of sliding distance and aspect ratio; and (3) a reduction in abductor activity up to 17.2% (gluteus medius). CONCLUSIONS: In our opinion, these potential biomechanical gains do not generally justify a fully medialised reconstruction, especially in younger patients that are more likely to undergo revision surgery in their lifetime. Cup medialisation should be performed until sufficient press fit and bony coverage of a properly sized and oriented cup can be achieved.

Ligamentum Teres Impingement in Valgus Impacted Femoral Neck Fracture: A Case for Hip Arthroscopy.

CASE: Seven years after hip arthroscopy for cam impingement, a 47-year-old female patient suffered a valgus impacted femoral neck fracture of her left hip that was stabilized with cannulated screws. After fracture healing, she experienced persisting sharp groin pain that could be elicited in flexion/internal rotation and extension/adduction. We suspected a ligamentum teres impingement at the border of the acetabular fossa due to a post-traumatic fovea alta and performed an arthroscopic ligament resection. Symptoms completely resolved thereafter. CONCLUSION: Valgus impacted femoral neck fractures with post-traumatic fovea alta may cause painful ligamentum teres impingement that can be treated with arthroscopic resection.

Electrosurgery Induced Femoral Stem Fracture in Total Hip Arthroplasty: A Case Report.

CASE: We present a case of a broken titanium alloy (Ti-6Al-7Nb) femoral stem 4 years after revision total hip arthroplasty (THA) (head exchange M to XL for instability). Material analysis showed a superficial anomaly on the superior neck surface caused by local melting with an electrosurgical knife. This lesion presumably acted as a stress riser and was the initiation site of a fatigue fracture, with typical features on the fracture surface. CONCLUSIONS: The use of electrosurgical knives in stem retaining THA revision surgery should be avoided, especially for surgical dissection in close proximity to the femoral stem.

Development of Bilateral Cam Deformity After Dunn Procedure and Contralateral Prophylactic Fixation: A Periosteal Reaction?: A Case Report.

CASE: We present the case of a fourteen-year-old male athlete with a slipped capital femoral epiphysis who was managed with a unilateral Dunn procedure and contralateral prophylactic screw fixation. Even though the cartilaginous epiphyseal growth plate was removed on one side, cam deformities subsequently developed on both sides in the postoperative period. CONCLUSION: This case suggests that structures other than the growth plate are also capable of inducing cam deformity of the hip.

Translaminar screw fixation of the lumbar spine: long-term outcome.

STUDY DESIGN: Retrospective clinical cohort study. OBJECTIVES: To evaluate the long-term results after translaminar screw fixation of the lumbar spine in a large group of patients and to identify predictors of a good outcome. SUMMARY OF BACKGROUND DATA: Translaminar screw fixation represents an alternative operative technique to transpedicular fixation systems for short-segment lumbar fusion. The strategy behind this technique is to block the facet joints with perforating screws. Although the method has been in use for more than 20 years, few studies reporting the long-term outcome in large groups of patients are to be found in the literature. METHODS: The Core Outcome Measures Index, a multidimensional outcome questionnaire, was sent to 643 consecutive patients who had undergone lumbar fusion with translaminar screws between 1987 and 2004, for various degenerative conditions of the lumbar spine. Patients also rated the global outcome and their satisfaction with treatment. Disc height was measured from preoperative radiographs using the distortion compensated roentgen analysis method. 476 patients (74%) completed and returned the questionnaire. Multiple logistic regression analysis was used to identify factors associated with a good outcome. RESULTS: After an average follow-up period of 10 years (range: 2-20 years) 352 of 476 patients (74%) reported that the operation had either "helped a lot" or "helped" (good outcome); 124 of 476 patients (26%) declared that it "helped only little," "didn't help," or "made things worse" (poor outcome). Controlling for potential confounders, a preoperative disc height <80% of that reported for a normal population was the most significant unique predictor of a good outcome (OR = 14.86, 95% CI: 6.77-32.61, P < 0.0001). CONCLUSION: Translaminar screw fixation is a straightforward and effective technique for short-segment fusion in the lumbar spine. For patients with a strict indication for spondylodesis, intact posterior elements (lamina and facets) and a low preoperative disc height, translaminar screw fixation represents a successful fixation technique in the lumbar spine with good long-term results.