Pudendal nerve neuralgia after hip arthroscopy: retrospective study and literature review

INTRODUCTION

Pudendal nerve neurapraxia is a classic complication after traction on the fracture table. Diagnosis, however, is difficult and often overlooked, especially after arthroscopy in traction on fracture table; incidence is therefore not known exactly.

HYPOTHESIS

The study hypothesis was that incidence of pudendal nerve neuropathy exceeds 1% after hip arthroscopy.

MATERIALS AND METHODS

Results for 150 patients (79 female, 71 male) undergoing hip arthroscopy between 2000 and 2010 were analyzed retrospectively. The principal assessment criterion was onset of pudendal neuralgia. Secondary criteria were risk factors (history, surgery time, type of anesthesia), associated complications, onset to diagnosis interval and pattern of evolution.

RESULTS

At a mean 93 months' follow-up, there were 3 cases (2 women, 1 man) (2%) of pure sensory pudendal neuralgia; 2 concerned labral lesion resection and 1 osteochondromatosis. Surgery time ranged from 60 to 120min, under general anesthesia with curarization. Time to diagnosis was 3 weeks. No complementary examinations were performed. Spontaneous resolution occurred at 3 weeks to 6 months. No significant risk factors emerged.

CONCLUSION

The present study found 2% incidence of pudendal neuralgia, with no risk factors emerging from analysis. Prevention involves limiting traction force and duration by using a large pelvic support (diameter>8-10cm). Patient information and postoperative screening should be systematic.

LEVEL OF EVIDENCE

Level IV. Retrospective study.

Obesity has no adverse effect on the outcome of unicompartmental knee replacement at a minimum follow-up of seven years

The significance of weight in the indications for unicompartmental knee replacement (UKR) is unclear. Our hypothesis was that weight does not affect the long-term rate of survival of UKRs. We undertook a retrospective study of 212 UKRs at a mean follow-up of 12 years (7 to 22). The patients were distributed according to body mass index (BMI; < vs ≥ 30 kg/m(2)) and weight (< vs ≥ 82 kg). Kaplan-Meier survivorship analysis was performed and ten-year survival rates were compared between the sub-groups. Multimodal regression analysis determined the impact of the various theoretical contraindications on the long-term rate of survival of UKR. The ten-year rates of survival were similar in the two weight subgroups (≥ 82 kg: 93.5% (95% confidence interval (CI) 66.5 to 96.3); < 82 kg: 92.5% (95% CI 82.5 to 94.1)) and also in the two BMI subgroups (≥ 30 kg/m(2): 92% (95% CI 82.5 to 95.3); < 30 kg/m(2): 94% (95% CI 78.4 to 95.9)). Multimodal regression analysis revealed that weight plays a part in reducing the risk of revision with a relative risk of 0.387, although this did not reach statistical significance (p = 0.662). The results relating weight and BMI to the clinical outcome were not statistically significant. Thus, this study confirms that weight does not influence the long-term rate of survival of UKR.

Fracture-dislocations of the femoral head

This review describes bone and nerve injury mechanisms during a femoral head fracture-dislocation and outlines a novel classification system that uses computed tomography scanning (CT scan) to help determine how to best treat these fractures in an emergency setting or in chronic cases. A series of 55 cases with CT scan performed in the emergency department (ED) and an average follow-up of 9 years (range 3-13) was used as a basis to develop the classification system; this system takes into account the size of the fragments and any associated acetabular wall or femoral neck fractures. The suggested course of action is based on the CT scan results after the hip joint is reduced. Conservative treatment is indicated every time the head fragments and any potential acetabular wall fragments are properly reduced and there are no foreign bodies (37.7%). Osteochondral head fragments below the fovea must be removed (36.3%). Fragments that are one-third or one-quarter of the head size can either be removed (7.2%) or reduced and fixed (5.4%). A novel medial approach is described that provides minimally invasive access to the anterior-inferior part of the femoral head, which should extend the indications for preservation of one-third head fragments. If the femoral neck is also fractured or a one-half head fragment exists in elderly patients, a total hip replacement should be considered right way (9%). At the latest follow-up, osteoarthritis was present in 43.7% of cases, but was mostly well tolerated - 94% of patients had a WOMAC score between 80 and 100 with signs of osteoarthritis visible on radiographs. Paradoxically, avascular necrosis (9%) is due to small head fractures. The results of our series are compared with the few series that have been published since CT scanning has been systematically used in the ED.

Is femoral head fracture-dislocation management improvable: A retrospective study in 110 cases

INTRODUCTION

There is no established consensus on the diagnosis and treatment of traumatic fracture-dislocation of the femoral head --largely due to the rarity of this injury.

HYPOTHESIS

Analysis of a large series of fracture-dislocations of the femoral head using a single coherent classification should enable the means of diagnosis and treatment of fracture-dislocations of the femoral head to be specified.

OBJECTIVES

The hypothesis was tested by analyzing a retrospective series of 110 patients charts admitted between 1972 and 2008, using Pipkin's classification and an alternative new one, Chiron's classification.

MATERIAL AND METHODS

The series comprised 21 women and 89 men; mean age: 37.1 years. Dislocation was posterior in 102 cases and anterior in eight. Associated lesions comprised 46 fractures of the acetabulum and four of the femoral neck. Classification following Pipkin and Chiron was based on double reading of radiology documents from 102 patients. Treatment was exclusively conservative in 32 cases, and surgical in 78, with 51 posterior, 19 anterior and four medial approaches and four arthroscopic procedures. Surgery comprised osteosynthesis of the femoral head in 30 cases and of the acetabulum in 16, removal of fragments in 40 cases and total hip replacement (THR) in five cases as a primary treatment.

RESULTS

Mean follow-up was 37 months. THR was performed in 25 cases: five as a primary treatment and 20 secondarily, 15 of which were performed within the first 6 months. Significant predictive factors for THR were: old age, Chiron grade 3, and femoral neck fracture. The THR and non-THR groups differed on the Chiron but not on the Pipkin classification at the time of the injury. Specific treatments were not predictive of evolution. Fragment removal was more often by a posterior than an anterior or medial approach.

CONCLUSION

The Chiron classification showed prognostic value for evolution to THR; to be reproducible, it needs to be based on CT data. No particular mode of treatment emerged as preferable. Better initial lesion analysis should enable prognosis and target indications.

LEVEL OF EVIDENCE

Level IV Retrospective study.

Ionic and energetic changes at competence in the naturally transformable bacterium Streptococcus pneumoniae

Addition of competence factor extracts to trigger competence in a culture of Streptococcus pneumoniae induced an increase in the intracellular pH and the Na+ content of the bacteria without any change in the K+ pool or in the membrane potential. These ionic shifts were concomitant with a stimulation of glycolysis that resulted in an enhanced ATP pool. Thus, in transforming conditions, at extracellular pH 7.8, competent bacteria presented a particularly high energetic state resulting from an increase in delta pH and in the ATP pool, associated with an enhanced Na+ content. These features are discussed in the context of homeostasis regulation in response to an environmental stimulus.